Typo.

scripts/win_wrapper.cmd

@@ -32,7 +32,7 @@ IF %MAJOR_PYTHON_VERSION% == 2 (
 ) ELSE IF %MAJOR_PYTHON_VERSION% == 3 (
     SET WINDOWS_SDK_VERSION="v7.1"
     IF %MINOR_PYTHON_VERSION% GEQ 5 (
-        SET SET_SDK_64=Y
+        SET NO_SET_SDK_64=Y
     )
 ) ELSE (
     ECHO Unsupported Python version: "%MAJOR_PYTHON_VERSION%"