diff --git a/api/windows_opengl.cpp b/api/windows_opengl.cpp
index 40625f6769..d92a2231e9 100755
--- a/api/windows_opengl.cpp
+++ b/api/windows_opengl.cpp
@@ -30,6 +30,7 @@
 #include <gl\glu.h>			// Header File For The GLu32 Library
 #include <stdio.h>
 
+#include "boinc_api.h"
 #include "graphics_api.h"
 #include "app_ipc.h"
 #include "util.h"