diff --git a/.appveyor.yml b/.appveyor.yml
index 01d3a758..d54511b1 100644
--- a/.appveyor.yml
+++ b/.appveyor.yml
@@ -40,9 +40,9 @@ test_script:
 
     } else {
 
-        msbuild /t:Build /p:platform=%platform%;configuration=%configuration% cryptlib.vcxproj
+        msbuild /t:Build /p:platform=$platform;configuration=$configuration cryptlib.vcxproj
 
-        msbuild /t:Build /p:platform=%platform%;configuration=%configuration% cryptest.vcxproj
+        msbuild /t:Build /p:platform=$platform;configuration=$configuration cryptest.vcxproj
 
         msbuild /t:CopyCryptestToRoot cryptest.vcxproj