diff --git a/appveyor.yml b/appveyor.yml
index 4e0214b5..590ad265 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,3 +1,5 @@
+os: Visual Studio 2013
+
 environment:
   CMAKE_ARGS: -DCMAKE_BUILD_TYPE=Release
   NSIS_ROOT: C:\nsis