diff --git a/src/activation.c b/src/activation.c
index d66f7ee..96db41a 100644
--- a/src/activation.c
+++ b/src/activation.c
@@ -44,6 +44,7 @@
 
 #ifdef WIN32
 #include <windows.h>
+#define strncasecmp _strnicmp
 #else
 #include <pthread.h>
 #endif