diff --git a/drivers/filters/mountmgr/mntmgr.h b/drivers/filters/mountmgr/mntmgr.h
index dacbfa7d69b..b92698fdeaf 100644
--- a/drivers/filters/mountmgr/mntmgr.h
+++ b/drivers/filters/mountmgr/mntmgr.h
@@ -176,6 +176,7 @@ extern UNICODE_STRING Volume;
 extern KEVENT UnloadEvent;
 extern LONG Unloading;
 
+INIT_FUNCTION
 DRIVER_INITIALIZE DriverEntry;
 
 VOID