diff --git a/appveyor.yml b/appveyor.yml
index 1acd2fa..c7e97ea 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -47,7 +47,7 @@ install:
 before_build:
   - mkdir %BUILD_HOME%
   - cd %BUILD_HOME%
-  - cmake -G %GENERATOR% 
+  - cmake -G "%GENERATOR%" 
     -DBOOST_ROOT="%BOOST_ROOT%"
     -DBoost_USE_STATIC_LIBS="ON" ..