diff --git a/MagickCore/studio.h b/MagickCore/studio.h
index a6039ec..c05e66c 100644
--- a/MagickCore/studio.h
+++ b/MagickCore/studio.h
@@ -70,7 +70,7 @@
 #  undef MAGICKCORE_BUILD_MODULES
 #endif
 
-#if defined(MAGICKCORE_WINDOWS_SUPPORT) || defined(__CYGWIN__) || defined(__MINGW32__)
+#if defined(MAGICKCORE_WINDOWS_SUPPORT) && !defined(__CYGWIN__)
 # define MagickPrivate
 # if defined(_MT) && defined(_DLL) && !defined(_MAGICKDLL_) && !defined(_LIB)
 #  define _MAGICKDLL_