diff --git a/scheduler/services.c b/scheduler/services.c
index 0b874e3b1e4..fccc97d8c7d 100644
--- a/scheduler/services.c
+++ b/scheduler/services.c
@@ -138,7 +138,7 @@ HANDLE SERVICE_AddObject( HANDLE object,
     SERVICE 		*s;
     HANDLE 		handle;
 
-    if ( object == INVALID_HANDLE_VALUE || !callback ) 
+    if ( !object || object == INVALID_HANDLE_VALUE || !callback ) 
         return INVALID_HANDLE_VALUE;
 
     if (!service_thread && !SERVICE_CreateServiceTable()) return INVALID_HANDLE_VALUE;