diff --git a/appveyor.yml b/appveyor.yml
index f7ada7f..e7f0893 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -42,7 +42,7 @@ before_build:
   - bash autogen.sh
   - mkdir build
   - cd build
-  - cmake .. -G "%GENERATOR%" -DBUILD_SHARED=%SHARED_LIBS% -DENABLE_VSTEST=%VSTEST%
+  - cmake .. -G "%GENERATOR%" -DBUILD_SHARED_LIBS=%SHARED_LIBS% -DENABLE_VSTEST=%VSTEST%
 
 build_script:
   - cmake --build . --config %CONFIG%