diff --git a/appveyor.yml b/appveyor.yml
index a22bc45..843da35 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -27,19 +27,19 @@ environment:
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       ADDPATH: C:\cygwin\bin;
       TOOLSET: gcc
-      CXXSTD: 03,11,14,1z
+      CXXSTD: 11,14,1z
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       ADDPATH: C:\cygwin64\bin;
       TOOLSET: gcc
-      CXXSTD: 03,11,14,1z
+      CXXSTD: 11,14,1z
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       ADDPATH: C:\mingw\bin;
       TOOLSET: gcc
-      CXXSTD: 03,11,14,1z
+      CXXSTD: 11,14,1z
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       ADDPATH: C:\mingw-w64\x86_64-6.3.0-posix-seh-rt_v5-rev1\mingw64\bin;
       TOOLSET: gcc
-      CXXSTD: 03,11,14,1z
+      CXXSTD: 11,14,1z
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2015
       CMAKE: 1
     - APPVEYOR_BUILD_WORKER_IMAGE: Visual Studio 2017