diff --git a/src/plugins/bineditor/bineditorplugin.cpp b/src/plugins/bineditor/bineditorplugin.cpp
index d70aa77cdf7..ae0f5362ce4 100644
--- a/src/plugins/bineditor/bineditorplugin.cpp
+++ b/src/plugins/bineditor/bineditorplugin.cpp
@@ -97,21 +97,20 @@ public:
         return type == TypeRemoved ? BehaviorSilent : IDocument::reloadBehavior(state, type);
     }
 
-    OpenResult open(QString *errorString, const FilePath &filePath,
-                    const FilePath &realFilePath) final
+    OpenResult open(const FilePath &filePath, const FilePath &realFilePath) final
     {
         QTC_CHECK(filePath == realFilePath); // The bineditor can do no autosaving
-        return openImpl(errorString, filePath);
+        return openImpl(filePath);
     }
 
-    OpenResult openImpl(QString *errorString, const FilePath &filePath, quint64 offset = 0);
+    OpenResult openImpl(const FilePath &filePath, quint64 offset = 0);
 
     void provideData(quint64 address);
 
     void provideNewRange(quint64 offset)
     {
         if (filePath().exists())
-            openImpl(nullptr, filePath(), offset);
+            openImpl(filePath(), offset);
     }
 
     bool isModified() const final;
@@ -2119,36 +2118,27 @@ bool BinEditorDocument::setContents(const QByteArray &contents)
     return true;
 }
 
-IDocument::OpenResult BinEditorDocument::openImpl(QString *errorString, const FilePath &filePath, quint64 offset)
+IDocument::OpenResult BinEditorDocument::openImpl(const FilePath &filePath, quint64 offset)
 {
     const qint64 size = filePath.fileSize();
     if (size < 0) {
         QString msg = Tr::tr("Cannot open %1: %2").arg(filePath.toUserOutput(), Tr::tr("File Error"));
         // FIXME: Was: file.errorString(), but we don't have a file anymore.
-        if (errorString)
-            *errorString = msg;
-        else
-            QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
-        return OpenResult::ReadError;
+        QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
+        return {OpenResult::ReadError, msg};
     }
 
     if (size == 0) {
         QString msg = Tr::tr("The Binary Editor cannot open empty files.");
-        if (errorString)
-            *errorString = msg;
-        else
-            QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
-        return OpenResult::CannotHandle;
+        QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
+        return {OpenResult::CannotHandle, msg};
     }
 
     if (size / 16 >= qint64(1) << 31) {
         // The limit is 2^31 lines (due to QText* interfaces) * 16 bytes per line.
         QString msg = Tr::tr("The file is too big for the Binary Editor (max. 32GB).");
-        if (errorString)
-            *errorString = msg;
-        else
-            QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
-        return OpenResult::CannotHandle;
+        QMessageBox::critical(ICore::dialogParent(), Tr::tr("File Error"), msg);
+        return {OpenResult::CannotHandle, msg};
     }
 
     if (offset >= quint64(size))
@@ -2189,10 +2179,9 @@ Result<> BinEditorDocument::reload(ReloadFlag flag, ChangeType type)
         return ResultOk;
     emit aboutToReload();
     clear();
-    QString errorString;
-    const bool success = (openImpl(&errorString, filePath()) == OpenResult::Success);
-    emit reloadFinished(success);
-    return makeResult(success, errorString);
+    const OpenResult result = openImpl(filePath());
+    emit reloadFinished(result.code == OpenResult::Success);
+    return result;
 }
 
 Result<> BinEditorDocument::saveImpl(const FilePath &filePath, bool autoSave)
diff --git a/src/plugins/clangformat/clangformatconfigwidget.cpp b/src/plugins/clangformat/clangformatconfigwidget.cpp
index d15e50fc8df..3d2ac617bc7 100644
--- a/src/plugins/clangformat/clangformatconfigwidget.cpp
+++ b/src/plugins/clangformat/clangformatconfigwidget.cpp
@@ -140,8 +140,7 @@ void ClangFormatConfigWidget::initEditor()
     Core::IEditorFactory *factory = factories.takeFirst();
     m_editor.reset(factory->createEditor());
 
-    QString errorString;
-    m_editor->document()->open(&errorString, m_config->filePath(), m_config->filePath());
+    m_editor->document()->open(m_config->filePath(), m_config->filePath());
     m_editor->widget()->adjustSize();
 
     invokeMethodForLanguageClientManager("documentOpened",
@@ -273,9 +272,8 @@ void ClangFormatConfigWidget::reopenClangFormatDocument()
 {
     GuardLocker locker(m_ignoreChanges);
 
-    QString errorString;
-    if (m_editor->document()->open(&errorString, m_config->filePath(), m_config->filePath())
-        == Core::IDocument::OpenResult::Success) {
+    if (m_editor->document()->open(m_config->filePath(), m_config->filePath()).code
+            == Core::IDocument::OpenResult::Success) {
         invokeMethodForLanguageClientManager("documentOpened",
                                              Q_ARG(Core::IDocument *, m_editor->document()));
     }
diff --git a/src/plugins/compilerexplorer/compilerexplorereditor.cpp b/src/plugins/compilerexplorer/compilerexplorereditor.cpp
index 2ea71e12f4b..6020e1a65bb 100644
--- a/src/plugins/compilerexplorer/compilerexplorereditor.cpp
+++ b/src/plugins/compilerexplorer/compilerexplorereditor.cpp
@@ -147,11 +147,11 @@ private:
 class JsonSettingsDocument : public Core::IDocument
 {
     Q_OBJECT
+
 public:
     JsonSettingsDocument(QUndoStack *undoStack);
 
-    OpenResult open(QString *errorString,
-                    const Utils::FilePath &filePath,
+    OpenResult open(const Utils::FilePath &filePath,
                     const Utils::FilePath &realFilePath) override;
 
     Result<> saveImpl(const Utils::FilePath &filePath, bool autoSave) override;
@@ -380,26 +380,19 @@ JsonSettingsDocument::JsonSettingsDocument(QUndoStack *undoStack)
     m_ceSettings.setUndoStack(undoStack);
 }
 
-Core::IDocument::OpenResult JsonSettingsDocument::open(QString *errorString,
-                                                       const FilePath &filePath,
-                                                       const FilePath &realFilePath)
+IDocument::OpenResult JsonSettingsDocument::open(const FilePath &filePath,
+                                                 const FilePath &realFilePath)
 {
     if (!filePath.isReadableFile())
         return OpenResult::ReadError;
 
-    auto contents = realFilePath.fileContents();
-    if (!contents) {
-        if (errorString)
-            *errorString = contents.error();
-        return OpenResult::ReadError;
-    }
+    Result<QByteArray> contents = realFilePath.fileContents();
+    if (!contents)
+        return {OpenResult::ReadError, contents.error()};
 
-    auto result = storeFromJson(*contents);
-    if (!result) {
-        if (errorString)
-            *errorString = result.error();
-        return OpenResult::ReadError;
-    }
+    Result<Store> result = storeFromJson(*contents);
+    if (!result)
+        return {OpenResult::ReadError, result.error()};
 
     setFilePath(filePath);
 
diff --git a/src/plugins/coreplugin/editormanager/editormanager.cpp b/src/plugins/coreplugin/editormanager/editormanager.cpp
index ceed445d0d9..3985f1ac16f 100644
--- a/src/plugins/coreplugin/editormanager/editormanager.cpp
+++ b/src/plugins/coreplugin/editormanager/editormanager.cpp
@@ -903,15 +903,14 @@ IEditor *EditorManagerPrivate::openEditor(EditorView *view, const FilePath &file
                 factory = factories.isEmpty() ? nullptr : factories.takeFirst();
                 continue;
             }
-            IDocument::OpenResult openResult = editor->document()->open(&errorString,
-                                                                        filePath,
-                                                                        realFp);
-            if (openResult == IDocument::OpenResult::Success)
+            IDocument::OpenResult openResult = editor->document()->open(filePath, realFp);
+            if (openResult.code == IDocument::OpenResult::Success)
                 break;
+            errorString = openResult.error;
             overrideCursor.reset();
             delete editor;
             editor = nullptr;
-            if (openResult == IDocument::OpenResult::ReadError) {
+            if (openResult.code == IDocument::OpenResult::ReadError) {
                 QMessageBox msgbox(QMessageBox::Critical,
                                    ::Core::Tr::tr("File Error"),
                                    ::Core::Tr::tr("Could not open \"%1\" for reading. "
@@ -924,7 +923,7 @@ IEditor *EditorManagerPrivate::openEditor(EditorView *view, const FilePath &file
                 return nullptr;
             }
             // can happen e.g. when trying to open an completely empty .qrc file
-            QTC_CHECK(openResult == IDocument::OpenResult::CannotHandle);
+            QTC_CHECK(openResult.code == IDocument::OpenResult::CannotHandle);
         } else {
             QTC_ASSERT(factory->isExternalEditor(),
                        factory = factories.isEmpty() ? nullptr : factories.takeFirst();
@@ -3019,7 +3018,7 @@ void EditorManager::runWithTemporaryEditor(const Utils::FilePath &filePath,
         if (!editor)
             continue;
         editor->document()->setTemporary(true);
-        if (editor->document()->open(nullptr, filePath, filePath) != IDocument::OpenResult::Success)
+        if (editor->document()->open(filePath, filePath).code != IDocument::OpenResult::Success)
             continue;
         callback(editor.get());
         break;
diff --git a/src/plugins/coreplugin/idocument.cpp b/src/plugins/coreplugin/idocument.cpp
index fe1ab0d8995..3774e2ad929 100644
--- a/src/plugins/coreplugin/idocument.cpp
+++ b/src/plugins/coreplugin/idocument.cpp
@@ -315,9 +315,8 @@ Id IDocument::id() const
     \sa shouldAutoSave()
     \sa setFilePath()
 */
-IDocument::OpenResult IDocument::open(QString *errorString, const Utils::FilePath &filePath, const Utils::FilePath &realFilePath)
+IDocument::OpenResult IDocument::open(const FilePath &filePath, const FilePath &realFilePath)
 {
-    Q_UNUSED(errorString)
     Q_UNUSED(filePath)
     Q_UNUSED(realFilePath)
     return OpenResult::CannotHandle;
@@ -808,4 +807,9 @@ QString IDocument::uniqueDisplayName() const
     return d->uniqueDisplayName;
 }
 
+IDocument::OpenResult::operator Result<>() const
+{
+    return makeResult(code == Success, error);
+}
+
 } // namespace Core
diff --git a/src/plugins/coreplugin/idocument.h b/src/plugins/coreplugin/idocument.h
index 58a903464a7..b28ef20094f 100644
--- a/src/plugins/coreplugin/idocument.h
+++ b/src/plugins/coreplugin/idocument.h
@@ -26,10 +26,23 @@ class CORE_EXPORT IDocument : public QObject
     Q_OBJECT
 
 public:
-    enum class OpenResult {
-        Success,
-        ReadError,
-        CannotHandle
+    class OpenResult
+    {
+    public:
+        enum Code {
+            Success,
+            ReadError,
+            CannotHandle
+        };
+
+        OpenResult() = default;
+        OpenResult(Code code) : code(code) {}
+        OpenResult(Code code, const QString &error) : code(code), error(error) {}
+
+        operator Utils::Result<>() const;
+
+        Code code;
+        QString error;
     };
 
     // This enum must match the indexes of the reloadBehavior widget
@@ -66,7 +79,7 @@ public:
     void setId(Utils::Id id);
     Utils::Id id() const;
 
-    virtual OpenResult open(QString *errorString, const Utils::FilePath &filePath, const Utils::FilePath &realFilePath);
+    virtual OpenResult open(const Utils::FilePath &filePath, const Utils::FilePath &realFilePath);
 
     Utils::Result<> save(const Utils::FilePath &filePath = {}, bool autoSave = false);
 
diff --git a/src/plugins/cppeditor/cpppointerdeclarationformatter_test.cpp b/src/plugins/cppeditor/cpppointerdeclarationformatter_test.cpp
index e6c9fc4f624..39c11c65f95 100644
--- a/src/plugins/cppeditor/cpppointerdeclarationformatter_test.cpp
+++ b/src/plugins/cppeditor/cpppointerdeclarationformatter_test.cpp
@@ -82,9 +82,8 @@ public:
 
         // Open file
         QScopedPointer<TextEditor::BaseTextEditor> editor(TextEditor::createPlainTextEditor());
-        QString error;
-        editor->document()->open(&error, document->filePath(), document->filePath());
-        QVERIFY(error.isEmpty());
+        Core::IDocument::OpenResult res = editor->document()->open(document->filePath(), document->filePath());
+        QVERIFY(res.error.isEmpty());
 
         // Set cursor position
         QTextCursor cursor = editor->textCursor();
diff --git a/src/plugins/designer/formwindowfile.cpp b/src/plugins/designer/formwindowfile.cpp
index d238a4002a4..b3b1bf10c17 100644
--- a/src/plugins/designer/formwindowfile.cpp
+++ b/src/plugins/designer/formwindowfile.cpp
@@ -19,10 +19,10 @@
 #include <QTextDocument>
 #include <QUndoStack>
 
+using namespace Core;
 using namespace Utils;
 
-namespace Designer {
-namespace Internal {
+namespace Designer::Internal {
 
 FormWindowFile::FormWindowFile(QDesignerFormWindowInterface *form, QObject *parent)
   : m_formWindow(form)
@@ -43,9 +43,8 @@ FormWindowFile::FormWindowFile(QDesignerFormWindowInterface *form, QObject *pare
             m_resourceHandler, &ResourceHandler::updateResources);
 }
 
-Core::IDocument::OpenResult FormWindowFile::open(QString *errorString,
-                                                 const Utils::FilePath &filePath,
-                                                 const Utils::FilePath &realFilePath)
+IDocument::OpenResult FormWindowFile::open(const FilePath &filePath,
+                                           const FilePath &realFilePath)
 {
     if (Designer::Constants::Internal::debug)
         qDebug() << "FormWindowFile::open" << filePath.toUserOutput();
@@ -57,21 +56,22 @@ Core::IDocument::OpenResult FormWindowFile::open(QString *errorString,
         return OpenResult::ReadError;
 
     QString contents;
-    Utils::TextFileFormat::ReadResult readResult = read(filePath.absoluteFilePath(),
-                                                        &contents,
-                                                        errorString);
+    QString errorString;
+    TextFileFormat::ReadResult readResult = read(filePath.absoluteFilePath(),
+                                                 &contents,
+                                                 &errorString);
     if (readResult == Utils::TextFileFormat::ReadEncodingError)
-        return OpenResult::CannotHandle;
+        return {OpenResult::CannotHandle, errorString};
     if (readResult != Utils::TextFileFormat::ReadSuccess)
-        return OpenResult::ReadError;
+        return {OpenResult::ReadError, errorString};
 
     form->setFileName(filePath.absoluteFilePath().toUrlishString());
     const QByteArray contentsBA = contents.toUtf8();
     QBuffer str;
     str.setData(contentsBA);
     str.open(QIODevice::ReadOnly);
-    if (!form->setContents(&str, errorString))
-        return OpenResult::CannotHandle;
+    if (!form->setContents(&str, &errorString))
+        return {OpenResult::CannotHandle, errorString};
     form->setDirty(filePath != realFilePath);
 
     syncXmlFromFormWindow();
@@ -201,11 +201,9 @@ Result<> FormWindowFile::reload(ReloadFlag flag, ChangeType type)
         return ResultOk;
     } else {
         emit aboutToReload();
-        QString errorString;
-        const bool success
-                = (open(&errorString, filePath(), filePath()) == OpenResult::Success);
-        emit reloadFinished(success);
-        return makeResult(success, errorString);
+        const OpenResult result = open(filePath(), filePath());
+        emit reloadFinished(result.code == OpenResult::Success);
+        return result;
     }
 }
 
@@ -269,5 +267,4 @@ void FormWindowFile::slotFormWindowRemoved(QDesignerFormWindowInterface *w)
         m_formWindow = nullptr;
 }
 
-} // namespace Internal
-} // namespace Designer
+} // namespace Designer::Internal
diff --git a/src/plugins/designer/formwindowfile.h b/src/plugins/designer/formwindowfile.h
index 289b338cec6..2a74c766518 100644
--- a/src/plugins/designer/formwindowfile.h
+++ b/src/plugins/designer/formwindowfile.h
@@ -26,7 +26,7 @@ public:
     ~FormWindowFile() override { }
 
     // IDocument
-    OpenResult open(QString *errorString, const Utils::FilePath &filePath,
+    OpenResult open(const Utils::FilePath &filePath,
                     const Utils::FilePath &realFilePath) override;
     QByteArray contents() const override;
     bool setContents(const QByteArray &contents) override;
diff --git a/src/plugins/diffeditor/diffeditordocument.cpp b/src/plugins/diffeditor/diffeditordocument.cpp
index 62176d3618b..fa9fc47bcfa 100644
--- a/src/plugins/diffeditor/diffeditordocument.cpp
+++ b/src/plugins/diffeditor/diffeditordocument.cpp
@@ -262,28 +262,26 @@ Result<> DiffEditorDocument::reload(ReloadFlag flag, ChangeType type)
     Q_UNUSED(type)
     if (flag == FlagIgnore)
         return ResultOk;
-    QString errorString;
-    bool success = open(&errorString, filePath(), filePath()) == OpenResult::Success;
-    return makeResult(success, errorString);
+    return open(filePath(), filePath());
 }
 
-Core::IDocument::OpenResult DiffEditorDocument::open(QString *errorString, const FilePath &filePath,
-                                                     const FilePath &realFilePath)
+IDocument::OpenResult DiffEditorDocument::open(const FilePath &filePath, const FilePath &realFilePath)
 {
     QTC_CHECK(filePath == realFilePath); // does not support autosave
     beginReload();
     QString patch;
-    ReadResult readResult = read(filePath, &patch, errorString);
+    QString errorString;
+    ReadResult readResult = read(filePath, &patch, &errorString);
     if (readResult == TextFileFormat::ReadIOError
         || readResult == TextFileFormat::ReadMemoryAllocationError) {
-        return OpenResult::ReadError;
+        return {OpenResult::ReadError, errorString};
     }
 
     const std::optional<QList<FileData>> fileDataList = DiffUtils::readPatch(patch);
     bool ok = fileDataList.has_value();
     if (!ok) {
-        *errorString = Tr::tr("Could not parse patch file \"%1\". "
-                              "The content is not of unified diff format.")
+        errorString = Tr::tr("Could not parse patch file \"%1\". "
+                             "The content is not of unified diff format.")
                 .arg(filePath.toUserOutput());
     } else {
         setTemporary(false);
@@ -295,7 +293,9 @@ Core::IDocument::OpenResult DiffEditorDocument::open(QString *errorString, const
     endReload(ok);
     if (!ok && readResult == TextFileFormat::ReadEncodingError)
         ok = selectEncoding();
-    return ok ? OpenResult::Success : OpenResult::CannotHandle;
+    if (!ok)
+        return {OpenResult::CannotHandle, errorString};
+    return OpenResult::Success;
 }
 
 bool DiffEditorDocument::selectEncoding()
diff --git a/src/plugins/diffeditor/diffeditordocument.h b/src/plugins/diffeditor/diffeditordocument.h
index 7a736ff929b..5c03c5ec01a 100644
--- a/src/plugins/diffeditor/diffeditordocument.h
+++ b/src/plugins/diffeditor/diffeditordocument.h
@@ -62,7 +62,7 @@ public:
     bool isSaveAsAllowed() const override;
     void reload();
     Utils::Result<> reload(ReloadFlag flag, ChangeType type) override;
-    OpenResult open(QString *errorString, const Utils::FilePath &filePath,
+    OpenResult open(const Utils::FilePath &filePath,
                     const Utils::FilePath &realFilePath) override;
     bool selectEncoding();
     State state() const { return m_state; }
diff --git a/src/plugins/imageviewer/imageviewerfile.cpp b/src/plugins/imageviewer/imageviewerfile.cpp
index 9eeee463951..b11b6a1a992 100644
--- a/src/plugins/imageviewer/imageviewerfile.cpp
+++ b/src/plugins/imageviewer/imageviewerfile.cpp
@@ -25,6 +25,7 @@
 #include <QGraphicsSvgItem>
 #endif
 
+using namespace Core;
 using namespace Utils;
 
 namespace ImageViewer::Internal {
@@ -63,18 +64,15 @@ ImageViewerFile::~ImageViewerFile()
     cleanUp();
 }
 
-Core::IDocument::OpenResult ImageViewerFile::open(QString *errorString,
-                                                  const Utils::FilePath &filePath,
-                                                  const Utils::FilePath &realfilePath)
+IDocument::OpenResult ImageViewerFile::open(const FilePath &filePath, const FilePath &realfilePath)
 {
     QTC_CHECK(filePath == realfilePath); // does not support auto save
-    OpenResult success = openImpl(errorString, filePath);
-    emit openFinished(success == OpenResult::Success);
-    return success;
+    OpenResult res = openImpl(filePath);
+    emit openFinished(res.code == OpenResult::Success);
+    return res;
 }
 
-Core::IDocument::OpenResult ImageViewerFile::openImpl(QString *errorString,
-                                                      const Utils::FilePath &filePath)
+IDocument::OpenResult ImageViewerFile::openImpl(const FilePath &filePath)
 {
     cleanUp();
 
@@ -84,11 +82,8 @@ Core::IDocument::OpenResult ImageViewerFile::openImpl(QString *errorString,
     const QString &fileName = filePath.toUrlishString();
     QByteArray format = QImageReader::imageFormat(fileName);
     // if it is impossible to recognize a file format - file will not be open correctly
-    if (format.isEmpty()) {
-        if (errorString)
-            *errorString = Tr::tr("Image format not supported.");
-        return OpenResult::CannotHandle;
-    }
+    if (format.isEmpty())
+        return {OpenResult::CannotHandle, Tr::tr("Image format not supported.")};
 
 #ifndef QT_NO_SVG
     if (format.startsWith("svg")) {
@@ -97,9 +92,7 @@ Core::IDocument::OpenResult ImageViewerFile::openImpl(QString *errorString,
         if (!bound.isValid() || (qFuzzyIsNull(bound.width()) && qFuzzyIsNull(bound.height()))) {
             delete m_tempSvgItem;
             m_tempSvgItem = nullptr;
-            if (errorString)
-                *errorString = Tr::tr("Failed to read SVG image.");
-            return OpenResult::CannotHandle;
+            return {OpenResult::CannotHandle, Tr::tr("Failed to read SVG image.")};
         }
         m_type = TypeSvg;
         emit imageSizeChanged(m_tempSvgItem->boundingRect().size().toSize());
@@ -110,11 +103,9 @@ Core::IDocument::OpenResult ImageViewerFile::openImpl(QString *errorString,
         // force reading movie/image data, so we can catch completely invalid movies/images early:
         m_movie->jumpToNextFrame();
         if (!m_movie->isValid()) {
-            if (errorString)
-                *errorString = Tr::tr("Failed to read image.");
             delete m_movie;
             m_movie = nullptr;
-            return OpenResult::CannotHandle;
+            return {OpenResult::CannotHandle, Tr::tr("Failed to read image.")};
         }
         m_type = TypeMovie;
         connect(m_movie, &QMovie::resized, this, &ImageViewerFile::imageSizeChanged);
@@ -122,11 +113,9 @@ Core::IDocument::OpenResult ImageViewerFile::openImpl(QString *errorString,
     } else {
         m_pixmap = new QPixmap(fileName);
         if (m_pixmap->isNull()) {
-            if (errorString)
-                *errorString = Tr::tr("Failed to read image.");
             delete m_pixmap;
             m_pixmap = nullptr;
-            return OpenResult::CannotHandle;
+            return {OpenResult::CannotHandle, Tr::tr("Failed to read image.")};
         }
         m_type = TypePixmap;
         emit imageSizeChanged(m_pixmap->size());
@@ -146,17 +135,15 @@ Core::IDocument::ReloadBehavior ImageViewerFile::reloadBehavior(ChangeTrigger st
     return BehaviorAsk;
 }
 
-Result<> ImageViewerFile::reload(Core::IDocument::ReloadFlag flag,
-                               Core::IDocument::ChangeType type)
+Result<> ImageViewerFile::reload(IDocument::ReloadFlag flag, IDocument::ChangeType type)
 {
     Q_UNUSED(type)
     if (flag == FlagIgnore)
         return ResultOk;
     emit aboutToReload();
-    QString errorString;
-    bool success = (openImpl(&errorString, filePath()) == OpenResult::Success);
-    emit reloadFinished(success);
-    return makeResult(success, errorString);
+    const OpenResult result = openImpl(filePath());
+    emit reloadFinished( result.code == OpenResult::Success);
+    return result;
 }
 
 QMovie *ImageViewerFile::movie() const
diff --git a/src/plugins/imageviewer/imageviewerfile.h b/src/plugins/imageviewer/imageviewerfile.h
index e4cc432651d..ea562341107 100644
--- a/src/plugins/imageviewer/imageviewerfile.h
+++ b/src/plugins/imageviewer/imageviewerfile.h
@@ -35,8 +35,7 @@ public:
     ImageViewerFile();
     ~ImageViewerFile() override;
 
-    OpenResult open(QString *errorString, const Utils::FilePath &filePath,
-                    const Utils::FilePath &realFilePath) override;
+    OpenResult open(const Utils::FilePath &filePath, const Utils::FilePath &realFilePath) override;
 
     ReloadBehavior reloadBehavior(ChangeTrigger state, ChangeType type) const override;
     Utils::Result<> reload(ReloadFlag flag, ChangeType type) override;
@@ -55,7 +54,7 @@ signals:
 
 private:
     void cleanUp();
-    OpenResult openImpl(QString *errorString, const Utils::FilePath &filePath);
+    OpenResult openImpl(const Utils::FilePath &filePath);
 
     ImageType m_type = TypeInvalid;
 #ifndef QT_NO_SVG
diff --git a/src/plugins/modeleditor/modeldocument.cpp b/src/plugins/modeleditor/modeldocument.cpp
index 3497d597f5b..980feff3fe3 100644
--- a/src/plugins/modeleditor/modeldocument.cpp
+++ b/src/plugins/modeleditor/modeldocument.cpp
@@ -19,10 +19,10 @@
 
 using namespace Utils;
 
-namespace ModelEditor {
-namespace Internal {
+namespace ModelEditor::Internal {
 
-class ModelDocument::ModelDocumentPrivate {
+class ModelDocument::ModelDocumentPrivate
+{
 public:
     ExtDocumentController *documentController = nullptr;
 };
@@ -42,13 +42,12 @@ ModelDocument::~ModelDocument()
     delete d;
 }
 
-Core::IDocument::OpenResult ModelDocument::open(QString *errorString,
-                                                const FilePath &filePath,
+Core::IDocument::OpenResult ModelDocument::open(const FilePath &filePath,
                                                 const FilePath &realFilePath)
 {
     Q_UNUSED(filePath)
 
-    OpenResult result = load(errorString, realFilePath);
+    OpenResult result = load(realFilePath);
     return result;
 }
 
@@ -112,7 +111,7 @@ ExtDocumentController *ModelDocument::documentController() const
     return d->documentController;
 }
 
-Core::IDocument::OpenResult ModelDocument::load(QString *errorString, const FilePath &fileName)
+Core::IDocument::OpenResult ModelDocument::load(const FilePath &fileName)
 {
     d->documentController = ModelEditorPlugin::modelsManager()->createModel(this);
     connect(d->documentController, &qmt::DocumentController::changed, this, &IDocument::changed);
@@ -121,11 +120,11 @@ Core::IDocument::OpenResult ModelDocument::load(QString *errorString, const File
         d->documentController->loadProject(fileName);
         setFilePath(d->documentController->projectController()->project()->fileName());
     } catch (const qmt::FileNotFoundException &ex) {
-        *errorString = ex.errorMessage();
-        return OpenResult::ReadError;
+        return {OpenResult::ReadError, ex.errorMessage()};
     } catch (const qmt::Exception &ex) {
-        *errorString = Tr::tr("Could not open \"%1\" for reading: %2.").arg(fileName.toUserOutput(), ex.errorMessage());
-        return OpenResult::CannotHandle;
+        return {OpenResult::CannotHandle,
+                    Tr::tr("Could not open \"%1\" for reading: %2.")
+                    .arg(fileName.toUserOutput(), ex.errorMessage())};
     }
 
     FilePath configPath = d->documentController->projectController()->project()->configPath();
@@ -143,5 +142,4 @@ Core::IDocument::OpenResult ModelDocument::load(QString *errorString, const File
     return OpenResult::Success;
 }
 
-} // namespace Internal
-} // namespace ModelEditor
+} // namespace ModelEditor::Internal
diff --git a/src/plugins/modeleditor/modeldocument.h b/src/plugins/modeleditor/modeldocument.h
index f36a32db80c..d6a06594db0 100644
--- a/src/plugins/modeleditor/modeldocument.h
+++ b/src/plugins/modeleditor/modeldocument.h
@@ -8,8 +8,7 @@
 
 namespace qmt { class Uid; }
 
-namespace ModelEditor {
-namespace Internal {
+namespace ModelEditor::Internal {
 
 class ExtDocumentController;
 
@@ -27,8 +26,7 @@ signals:
     void contentSet();
 
 public:
-    OpenResult open(QString *errorString,
-                    const Utils::FilePath &filePath,
+    OpenResult open(const Utils::FilePath &filePath,
                     const Utils::FilePath &realFilePath) override;
     bool shouldAutoSave() const override;
     bool isModified() const override;
@@ -37,7 +35,7 @@ public:
 
     ExtDocumentController *documentController() const;
 
-    OpenResult load(QString *errorString, const Utils::FilePath &fileName);
+    OpenResult load(const Utils::FilePath &fileName);
 
 protected:
     Utils::Result<> saveImpl(const Utils::FilePath &filePath, bool autoSave) override;
@@ -46,5 +44,4 @@ private:
     ModelDocumentPrivate *d;
 };
 
-} // namespace Internal
-} // namespace ModelEditor
+} // namespace ModelEditor::Internal
diff --git a/src/plugins/resourceeditor/qrceditor/resourcefile.cpp b/src/plugins/resourceeditor/qrceditor/resourcefile.cpp
index dae3bd562aa..c8e74c8c9ac 100644
--- a/src/plugins/resourceeditor/qrceditor/resourcefile.cpp
+++ b/src/plugins/resourceeditor/qrceditor/resourcefile.cpp
@@ -1081,7 +1081,7 @@ Core::IDocument::OpenResult ResourceModel::reload()
 {
     beginResetModel();
     Core::IDocument::OpenResult result = m_resource_file.load();
-    if (result == Core::IDocument::OpenResult::Success)
+    if (result.code == Core::IDocument::OpenResult::Success)
         setDirty(false);
     endResetModel();
     return result;
diff --git a/src/plugins/resourceeditor/resourceeditor.cpp b/src/plugins/resourceeditor/resourceeditor.cpp
index 297cf682933..463927b64c8 100644
--- a/src/plugins/resourceeditor/resourceeditor.cpp
+++ b/src/plugins/resourceeditor/resourceeditor.cpp
@@ -48,8 +48,7 @@ class ResourceEditorDocument final : public IDocument
 public:
     ResourceEditorDocument(QObject *parent = nullptr);
 
-    OpenResult open(QString *errorString, const FilePath &filePath,
-                    const FilePath &realFilePath) final;
+    OpenResult open(const FilePath &filePath, const FilePath &realFilePath) final;
     QString plainText() const { return m_model.contents(); }
     QByteArray contents() const final { return m_model.contents().toUtf8(); }
     bool setContents(const QByteArray &contents) final;
@@ -180,8 +179,7 @@ ResourceEditorImpl::~ResourceEditorImpl()
     delete m_toolBar;
 }
 
-IDocument::OpenResult ResourceEditorDocument::open(QString *errorString,
-                                                   const FilePath &filePath,
+IDocument::OpenResult ResourceEditorDocument::open(const FilePath &filePath,
                                                    const FilePath &realFilePath)
 {
     if (debugResourceEditorW)
@@ -192,9 +190,8 @@ IDocument::OpenResult ResourceEditorDocument::open(QString *errorString,
     m_model.setFilePath(realFilePath);
 
     OpenResult openResult = m_model.reload();
-    if (openResult != OpenResult::Success) {
-        if (errorString)
-            *errorString = m_model.errorMessage();
+    if (openResult.code != OpenResult::Success) {
+        openResult.error = m_model.errorMessage();
         setBlockDirtyChanged(false);
         emit loaded(false);
         return openResult;
@@ -249,7 +246,7 @@ bool ResourceEditorDocument::setContents(const QByteArray &contents)
 
     const FilePath originalFileName = m_model.filePath();
     m_model.setFilePath(saver.filePath());
-    const bool success = (m_model.reload() == OpenResult::Success);
+    const bool success = (m_model.reload().code == OpenResult::Success);
     m_model.setFilePath(originalFileName);
     m_shouldAutoSave = false;
     if (debugResourceEditorW)
@@ -286,10 +283,9 @@ Result<> ResourceEditorDocument::reload(ReloadFlag flag, ChangeType type)
     if (flag == FlagIgnore)
         return ResultOk;
     emit aboutToReload();
-    QString errorString;
-    const bool success = (open(&errorString, filePath(), filePath()) == OpenResult::Success);
-    emit reloadFinished(success);
-    return makeResult(success, errorString);
+    const OpenResult result = open(filePath(), filePath());
+    emit reloadFinished(result.code == OpenResult::Success);
+    return result;
 }
 
 void ResourceEditorDocument::dirtyChanged(bool dirty)
diff --git a/src/plugins/resourceeditor/resourcenode.cpp b/src/plugins/resourceeditor/resourcenode.cpp
index d27a7cb992c..5411ac9a0f7 100644
--- a/src/plugins/resourceeditor/resourcenode.cpp
+++ b/src/plugins/resourceeditor/resourcenode.cpp
@@ -121,7 +121,7 @@ static bool addFilesToResource(const FilePath &resourceFile,
         *notAdded = filePaths;
 
     ResourceFile file(resourceFile);
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
 
     int index = file.indexOfPrefix(prefix, lang);
@@ -272,7 +272,7 @@ static void compressTree(FolderNode *n)
 void ResourceTopLevelNode::addInternalNodes()
 {
     ResourceFile file(filePath(), m_contents);
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return;
 
     QMap<PrefixFolderLang, FolderNode *> folderNodes;
@@ -382,7 +382,7 @@ RemovedFilesFromProject ResourceTopLevelNode::removeFiles(const FilePaths &fileP
 bool ResourceTopLevelNode::addPrefix(const QString &prefix, const QString &lang)
 {
     ResourceFile file(filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
     int index = file.addPrefix(prefix, lang);
     if (index == -1)
@@ -395,7 +395,7 @@ bool ResourceTopLevelNode::addPrefix(const QString &prefix, const QString &lang)
 bool ResourceTopLevelNode::removePrefix(const QString &prefix, const QString &lang)
 {
     ResourceFile file(filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
     for (int i = 0; i < file.prefixCount(); ++i) {
         if (file.prefix(i) == prefix
@@ -411,7 +411,7 @@ bool ResourceTopLevelNode::removePrefix(const QString &prefix, const QString &la
 bool ResourceTopLevelNode::removeNonExistingFiles()
 {
     ResourceFile file(filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
 
     QFileInfo fi;
@@ -490,7 +490,7 @@ RemovedFilesFromProject ResourceFolderNode::removeFiles(const FilePaths &filePat
     if (notRemoved)
         *notRemoved = filePaths;
     ResourceFile file(m_topLevelNode->filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return RemovedFilesFromProject::Error;
     int index = file.indexOfPrefix(m_prefix, m_lang);
     if (index == -1)
@@ -518,7 +518,8 @@ bool ResourceFolderNode::canRenameFile(const FilePath &oldFilePath, const FilePa
     bool fileEntryExists = false;
     ResourceFile file(m_topLevelNode->filePath());
 
-    int index = (file.load() != IDocument::OpenResult::Success) ? -1 :file.indexOfPrefix(m_prefix, m_lang);
+    int index = (file.load().code != IDocument::OpenResult::Success)
+            ? -1 : file.indexOfPrefix(m_prefix, m_lang);
     if (index != -1) {
         for (int j = 0; j < file.fileCount(index); ++j) {
             if (file.file(index, j) == oldFilePath.toUrlishString()) {
@@ -534,7 +535,7 @@ bool ResourceFolderNode::canRenameFile(const FilePath &oldFilePath, const FilePa
 bool ResourceFolderNode::renameFiles(const FilePairs &filesToRename, FilePaths *notRenamed)
 {
     ResourceFile file(m_topLevelNode->filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
     int index = file.indexOfPrefix(m_prefix, m_lang);
     if (index == -1)
@@ -566,7 +567,7 @@ bool ResourceFolderNode::renameFiles(const FilePairs &filesToRename, FilePaths *
 bool ResourceFolderNode::renamePrefix(const QString &prefix, const QString &lang)
 {
     ResourceFile file(m_topLevelNode->filePath());
-    if (file.load() != IDocument::OpenResult::Success)
+    if (file.load().code != IDocument::OpenResult::Success)
         return false;
     int index = file.indexOfPrefix(m_prefix, m_lang);
     if (index == -1)
diff --git a/src/plugins/scxmleditor/scxmleditordocument.cpp b/src/plugins/scxmleditor/scxmleditordocument.cpp
index 3102e8008b5..4eff969c391 100644
--- a/src/plugins/scxmleditor/scxmleditordocument.cpp
+++ b/src/plugins/scxmleditor/scxmleditordocument.cpp
@@ -18,7 +18,8 @@
 using namespace Utils;
 
 using namespace ScxmlEditor::Common;
-using namespace ScxmlEditor::Internal;
+
+namespace ScxmlEditor::Internal {
 
 ScxmlEditorDocument::ScxmlEditorDocument(MainWidget *designWidget, QObject *parent)
     : m_designWidget(designWidget)
@@ -34,9 +35,8 @@ ScxmlEditorDocument::ScxmlEditorDocument(MainWidget *designWidget, QObject *pare
     });
 }
 
-Core::IDocument::OpenResult ScxmlEditorDocument::open(QString *errorString,
-                                                      const Utils::FilePath &filePath,
-                                                      const Utils::FilePath &realFilePath)
+Core::IDocument::OpenResult ScxmlEditorDocument::open(const FilePath &filePath,
+                                                      const FilePath &realFilePath)
 {
     Q_UNUSED(realFilePath)
 
@@ -47,10 +47,8 @@ Core::IDocument::OpenResult ScxmlEditorDocument::open(QString *errorString,
         return OpenResult::ReadError;
 
     const FilePath &absoluteFilePath = filePath.absoluteFilePath();
-    if (!m_designWidget->load(absoluteFilePath.toUrlishString())) {
-        *errorString = m_designWidget->errorMessage();
-        return OpenResult::ReadError;
-    }
+    if (!m_designWidget->load(absoluteFilePath.toUrlishString()))
+        return {OpenResult::ReadError, m_designWidget->errorMessage()};
 
     setFilePath(absoluteFilePath);
 
@@ -137,3 +135,5 @@ void ScxmlEditorDocument::syncXmlFromDesignWidget()
 {
     document()->setPlainText(designWidgetContents());
 }
+
+} // namespace ScxmlEditor::Internal
diff --git a/src/plugins/scxmleditor/scxmleditordocument.h b/src/plugins/scxmleditor/scxmleditordocument.h
index ba4cfc42d6a..70d93d2ab72 100644
--- a/src/plugins/scxmleditor/scxmleditordocument.h
+++ b/src/plugins/scxmleditor/scxmleditordocument.h
@@ -13,9 +13,7 @@ QT_FORWARD_DECLARE_CLASS(QDesignerFormWindowInterface)
 
 namespace ScxmlEditor {
 
-namespace Common {
-class MainWidget;
-} // namespace Common
+namespace Common { class MainWidget; }
 
 namespace Internal {
 
@@ -27,9 +25,7 @@ public:
     explicit ScxmlEditorDocument(Common::MainWidget *designWidget, QObject *parent = nullptr);
 
     // IDocument
-    OpenResult open(QString *errorString,
-                    const Utils::FilePath &filePath,
-                    const Utils::FilePath &realFilePath) override;
+    OpenResult open(const Utils::FilePath &filePath, const Utils::FilePath &realFilePath) override;
     bool shouldAutoSave() const override;
     bool isSaveAsAllowed() const override;
     bool isModified() const override;
diff --git a/src/plugins/squish/objectsmapdocument.cpp b/src/plugins/squish/objectsmapdocument.cpp
index 53c5cba6e56..7146e10bba0 100644
--- a/src/plugins/squish/objectsmapdocument.cpp
+++ b/src/plugins/squish/objectsmapdocument.cpp
@@ -11,10 +11,10 @@
 #include <utils/fileutils.h>
 #include <utils/qtcprocess.h>
 
+using namespace Core;
 using namespace Utils;
 
-namespace Squish {
-namespace Internal {
+namespace Squish::Internal {
 
 static const char kItemSeparator = '\n';
 static const char kPropertySeparator = '\t';
@@ -28,12 +28,11 @@ ObjectsMapDocument::ObjectsMapDocument()
     connect(m_contentModel, &ObjectsMapModel::modelChanged, this, [this] { setModified(true); });
 }
 
-Core::IDocument::OpenResult ObjectsMapDocument::open(QString *errorString,
-                                                     const Utils::FilePath &fileName,
-                                                     const Utils::FilePath &realFileName)
+IDocument::OpenResult ObjectsMapDocument::open(const FilePath &fileName,
+                                               const FilePath &realFileName)
 {
-    OpenResult result = openImpl(errorString, fileName, realFileName);
-    if (result == OpenResult::Success) {
+    OpenResult result = openImpl(fileName, realFileName);
+    if (result.code == OpenResult::Success) {
         setFilePath(fileName);
         setModified(fileName != realFileName);
     }
@@ -72,19 +71,18 @@ void ObjectsMapDocument::setModified(bool modified)
     emit changed();
 }
 
-Result<> ObjectsMapDocument::reload(Core::IDocument::ReloadFlag flag,
-                                  Core::IDocument::ChangeType type)
+Result<> ObjectsMapDocument::reload(IDocument::ReloadFlag flag, IDocument::ChangeType type)
 {
     Q_UNUSED(type)
     if (flag == FlagIgnore)
         return ResultOk;
     emit aboutToReload();
-    QString errorString;
-    const bool success = (openImpl(&errorString, filePath(), filePath()) == OpenResult::Success);
+    const OpenResult result = openImpl(filePath(), filePath());
+    const bool success = result.code == OpenResult::Success;
     if (success)
         setModified(false);
     emit reloadFinished(success);
-    return makeResult(success, errorString);
+    return result;
 }
 
 bool ObjectsMapDocument::buildObjectsMapTree(const QByteArray &contents)
@@ -175,36 +173,31 @@ QByteArray ObjectsMapDocument::contents() const
     return result;
 }
 
-Core::IDocument::OpenResult ObjectsMapDocument::openImpl(QString *error,
-                                                         const Utils::FilePath &fileName,
-                                                         const Utils::FilePath &realFileName)
+IDocument::OpenResult ObjectsMapDocument::openImpl(const FilePath &fileName,
+                                                   const FilePath &realFileName)
 {
     if (fileName.isEmpty())
         return OpenResult::CannotHandle;
 
     QByteArray text;
     if (realFileName.fileName() == "objects.map") {
-        Utils::FileReader reader;
-        if (!reader.fetch(realFileName, error))
-            return OpenResult::ReadError;
+        FileReader reader;
+        if (const Result<> res = reader.fetch(realFileName); !res)
+            return {OpenResult::ReadError, res.error()};
 
         text = reader.text();
     } else {
-        const Utils::FilePath base = settings().squishPath();
+        const FilePath base = settings().squishPath();
         if (base.isEmpty()) {
-            if (error)
-                error->append(Tr::tr("Incomplete Squish settings. "
-                                     "Missing Squish installation path."));
-            return OpenResult::ReadError;
-        }
-        const Utils::FilePath exe = base.pathAppended("lib/exec/objectmaptool").withExecutableSuffix();
-        if (!exe.isExecutableFile()) {
-            if (error)
-                error->append(Tr::tr("objectmaptool not found."));
-            return OpenResult::ReadError;
+            return {OpenResult::ReadError, Tr::tr("Incomplete Squish settings. "
+                                     "Missing Squish installation path.")};
         }
+        const FilePath exe = base.pathAppended("lib/exec/objectmaptool").withExecutableSuffix();
+        if (!exe.isExecutableFile())
+            return {OpenResult::ReadError, Tr::tr("objectmaptool not found.")};
 
-        Utils::Process objectMapReader;
+
+        Process objectMapReader;
         objectMapReader.setCommand({exe, {"--scriptMap", "--mode", "read",
                                           "--scriptedObjectMapPath", realFileName.toUserOutput()}});
         objectMapReader.setUtf8Codec();
@@ -212,11 +205,8 @@ Core::IDocument::OpenResult ObjectsMapDocument::openImpl(QString *error,
         objectMapReader.waitForFinished();
         text = objectMapReader.cleanedStdOut().toUtf8();
     }
-    if (!setContents(text)) {
-        if (error)
-            error->append(Tr::tr("Failure while parsing objects.map content."));
-        return OpenResult::ReadError;
-    }
+    if (!setContents(text))
+        return {OpenResult::ReadError, Tr::tr("Failure while parsing objects.map content.")};
     return OpenResult::Success;
 }
 
@@ -244,5 +234,4 @@ bool ObjectsMapDocument::writeFile(const Utils::FilePath &fileName) const
     return objectMapWriter.result() == Utils::ProcessResult::FinishedWithSuccess;
 }
 
-} // namespace Internal
-} // namespace Squish
+} // namespace Squish::Internal
diff --git a/src/plugins/squish/objectsmapdocument.h b/src/plugins/squish/objectsmapdocument.h
index f24b47c4f61..b8355464ecc 100644
--- a/src/plugins/squish/objectsmapdocument.h
+++ b/src/plugins/squish/objectsmapdocument.h
@@ -7,8 +7,7 @@
 
 #include <QList>
 
-namespace Squish {
-namespace Internal {
+namespace Squish::Internal {
 
 class ObjectsMapModel;
 
@@ -18,8 +17,7 @@ class ObjectsMapDocument : public Core::IDocument
 public:
     ObjectsMapDocument();
 
-    OpenResult open(QString *errorString,
-                    const Utils::FilePath &fileName,
+    OpenResult open(const Utils::FilePath &fileName,
                     const Utils::FilePath &realFileName) override;
     Utils::FilePath fallbackSaveAsPath() const override;
     QString fallbackSaveAsFileName() const override;
@@ -37,8 +35,7 @@ protected:
     Utils::Result<> saveImpl(const Utils::FilePath &fileName, bool autoSave) override;
 
 private:
-    OpenResult openImpl(QString *error,
-                        const Utils::FilePath &fileName,
+    OpenResult openImpl(const Utils::FilePath &fileName,
                         const Utils::FilePath &realFileName);
     bool buildObjectsMapTree(const QByteArray &contents);
     bool writeFile(const Utils::FilePath &fileName) const;
@@ -48,5 +45,4 @@ private:
     bool m_isModified;
 };
 
-} // namespace Internal
-} // namespace Squish
+} // namespace Squish::Internal
diff --git a/src/plugins/texteditor/textdocument.cpp b/src/plugins/texteditor/textdocument.cpp
index d2567b3bbf5..4e23e9a7512 100644
--- a/src/plugins/texteditor/textdocument.cpp
+++ b/src/plugins/texteditor/textdocument.cpp
@@ -754,31 +754,29 @@ bool TextDocument::isModified() const
     return d->m_document.isModified();
 }
 
-Core::IDocument::OpenResult TextDocument::open(QString *errorString,
-                                               const Utils::FilePath &filePath,
-                                               const Utils::FilePath &realFilePath)
+IDocument::OpenResult TextDocument::open(const FilePath &filePath, const FilePath &realFilePath)
 {
     emit aboutToOpen(filePath, realFilePath);
-    OpenResult success = openImpl(errorString, filePath, realFilePath, /*reload =*/ false);
-    if (success == OpenResult::Success) {
+    OpenResult result = openImpl(filePath, realFilePath, /*reload =*/ false);
+    if (result.code == OpenResult::Success) {
         setMimeType(Utils::mimeTypeForFile(filePath, MimeMatchMode::MatchDefaultAndRemote).name());
         setTabSettings(d->m_tabSettings);
         emit openFinishedSuccessfully();
     }
-    return success;
+    return result;
 }
 
-Core::IDocument::OpenResult TextDocument::openImpl(QString *errorString,
-                                                   const Utils::FilePath &filePath,
-                                                   const Utils::FilePath &realFilePath,
-                                                   bool reload)
+IDocument::OpenResult TextDocument::openImpl(const FilePath &filePath,
+                                             const FilePath &realFilePath,
+                                             bool reload)
 {
     QStringList content;
+    QString errorString;
 
-    ReadResult readResult = Utils::TextFileFormat::ReadIOError;
+    ReadResult readResult = TextFileFormat::ReadIOError;
 
     if (!filePath.isEmpty()) {
-        readResult = read(realFilePath, &content, errorString);
+        readResult = read(realFilePath, &content, &errorString);
         const int chunks = content.size();
 
         // Don't call setUndoRedoEnabled(true) when reload is true and filenames are different,
@@ -829,7 +827,7 @@ Core::IDocument::OpenResult TextDocument::openImpl(QString *errorString,
         setFilePath(filePath);
     }
     if (readResult == Utils::TextFileFormat::ReadIOError)
-        return OpenResult::ReadError;
+        return {OpenResult::ReadError, errorString};
     return OpenResult::Success;
 }
 
@@ -853,15 +851,13 @@ Result<> TextDocument::reload(const FilePath &realFilePath)
     if (documentLayout)
         documentLayout->documentAboutToReload(this); // removes text marks non-permanently
 
-    QString errorString;
-    bool success = openImpl(&errorString, filePath(), realFilePath, /*reload =*/true)
-                   == OpenResult::Success;
+    const OpenResult result = openImpl(filePath(), realFilePath, /*reload =*/true);
 
     if (documentLayout)
         documentLayout->documentReloaded(this); // re-adds text marks
-    emit reloadFinished(success);
+    emit reloadFinished(result.code == OpenResult::Success);
 
-    return makeResult(success, errorString);
+    return result;
 }
 
 bool TextDocument::setPlainText(const QString &text)
diff --git a/src/plugins/texteditor/textdocument.h b/src/plugins/texteditor/textdocument.h
index 3d5b8ea9baf..65285dc1c83 100644
--- a/src/plugins/texteditor/textdocument.h
+++ b/src/plugins/texteditor/textdocument.h
@@ -117,8 +117,7 @@ public:
     void setFallbackSaveAsPath(const Utils::FilePath &fallbackSaveAsPath);
     void setFallbackSaveAsFileName(const QString &fallbackSaveAsFileName);
 
-    OpenResult open(QString *errorString, const Utils::FilePath &filePath,
-                    const Utils::FilePath &realFilePath) override;
+    OpenResult open(const Utils::FilePath &filePath, const Utils::FilePath &realFilePath) override;
     virtual Utils::Result<> reload();
     Utils::Result<> reload(const Utils::FilePath &realFilePath);
 
@@ -170,8 +169,7 @@ protected:
     virtual void slotCodeStyleSettingsChanged(); // Used in CppEditorDocumet
 
 private:
-    OpenResult openImpl(QString *errorString,
-                        const Utils::FilePath &filePath,
+    OpenResult openImpl(const Utils::FilePath &filePath,
                         const Utils::FilePath &realFileName,
                         bool reload);
     void cleanWhitespace(QTextCursor &cursor, bool inEntireDocument, bool cleanIndentation);
diff --git a/src/plugins/vcsbase/submiteditorfile.cpp b/src/plugins/vcsbase/submiteditorfile.cpp
index ca5601a8002..be85fed0cd9 100644
--- a/src/plugins/vcsbase/submiteditorfile.cpp
+++ b/src/plugins/vcsbase/submiteditorfile.cpp
@@ -27,15 +27,14 @@ SubmitEditorFile::SubmitEditorFile(VcsBaseSubmitEditor *editor) :
             this, &IDocument::contentsChanged);
 }
 
-IDocument::OpenResult SubmitEditorFile::open(QString *errorString, const FilePath &filePath,
-                                             const FilePath &realFilePath)
+IDocument::OpenResult SubmitEditorFile::open(const FilePath &filePath, const FilePath &realFilePath)
 {
     if (filePath.isEmpty())
         return OpenResult::ReadError;
 
     FileReader reader;
-    if (!reader.fetch(realFilePath, errorString))
-        return OpenResult::ReadError;
+    if (const Result<> res = reader.fetch(realFilePath); !res)
+        return {OpenResult::ReadError, res.error()};
 
     const QString text = QString::fromLocal8Bit(reader.text());
     if (!m_editor->setFileContents(text.toUtf8()))
diff --git a/src/plugins/vcsbase/submiteditorfile.h b/src/plugins/vcsbase/submiteditorfile.h
index de9741a1fdf..398138d6dee 100644
--- a/src/plugins/vcsbase/submiteditorfile.h
+++ b/src/plugins/vcsbase/submiteditorfile.h
@@ -17,8 +17,8 @@ class SubmitEditorFile : public Core::IDocument
 public:
     explicit SubmitEditorFile(VcsBaseSubmitEditor *editor);
 
-    OpenResult open(QString *errorString, const Utils::FilePath &filePath,
-                    const Utils::FilePath &realFilePath) override;
+    OpenResult open(const Utils::FilePath &filePath, const Utils::FilePath &realFilePath) override;
+
     QByteArray contents() const override;
     bool setContents(const QByteArray &contents) override;