diff --git a/include/boost/intrusive/detail/assert.hpp b/include/boost/intrusive/detail/assert.hpp
index 3dacbcc..d75d225 100644
--- a/include/boost/intrusive/detail/assert.hpp
+++ b/include/boost/intrusive/detail/assert.hpp
@@ -13,7 +13,7 @@
 #ifndef BOOST_INTRUSIVE_DETAIL_ASSERT_HPP
 #define BOOST_INTRUSIVE_DETAIL_ASSERT_HPP
 
-#if defined(_MSC_VER)&&(_MSC_VER>=1200)
+#if defined(_MSC_VER)
 #pragma once
 #endif
 
diff --git a/include/boost/intrusive/detail/memory_util.hpp b/include/boost/intrusive/detail/memory_util.hpp
index bfc9b14..e644ebc 100644
--- a/include/boost/intrusive/detail/memory_util.hpp
+++ b/include/boost/intrusive/detail/memory_util.hpp
@@ -17,7 +17,7 @@
 #ifndef BOOST_INTRUSIVE_ALLOCATOR_MEMORY_UTIL_HPP
 #define BOOST_INTRUSIVE_ALLOCATOR_MEMORY_UTIL_HPP
 
-#if (defined _MSC_VER) && (_MSC_VER >= 1200)
+#if defined(_MSC_VER)
 #  pragma once
 #endif
 
diff --git a/include/boost/intrusive/detail/preprocessor.hpp b/include/boost/intrusive/detail/preprocessor.hpp
index b3ed6e6..b8143a4 100644
--- a/include/boost/intrusive/detail/preprocessor.hpp
+++ b/include/boost/intrusive/detail/preprocessor.hpp
@@ -11,7 +11,7 @@
 #ifndef BOOST_INTRUSIVE_DETAIL_PREPROCESSOR_HPP
 #define BOOST_INTRUSIVE_DETAIL_PREPROCESSOR_HPP
 
-#if (defined _MSC_VER) && (_MSC_VER >= 1200)
+#if defined(_MSC_VER)
 #  pragma once
 #endif
 
diff --git a/include/boost/intrusive/pointer_traits.hpp b/include/boost/intrusive/pointer_traits.hpp
index 21b14a1..beebe6b 100644
--- a/include/boost/intrusive/pointer_traits.hpp
+++ b/include/boost/intrusive/pointer_traits.hpp
@@ -17,7 +17,7 @@
 #ifndef BOOST_INTRUSIVE_POINTER_TRAITS_HPP
 #define BOOST_INTRUSIVE_POINTER_TRAITS_HPP
 
-#if (defined _MSC_VER) && (_MSC_VER >= 1200)
+#if defined(_MSC_VER)
 #  pragma once
 #endif
 
diff --git a/test/smart_ptr.hpp b/test/smart_ptr.hpp
index cea8e90..c226b5b 100644
--- a/test/smart_ptr.hpp
+++ b/test/smart_ptr.hpp
@@ -16,7 +16,7 @@
 #include <boost/pointer_cast.hpp>
 #include <boost/intrusive/pointer_traits.hpp>
 
-#if (defined _MSC_VER) && (_MSC_VER >= 1200)
+#if (defined _MSC_VER)
 #  pragma once
 #endif