diff --git a/src/libCom/osi/os/WIN32/osdThread.c b/src/libCom/osi/os/WIN32/osdThread.c
index 431aeddbe..2f417553e 100644
--- a/src/libCom/osi/os/WIN32/osdThread.c
+++ b/src/libCom/osi/os/WIN32/osdThread.c
@@ -560,7 +560,7 @@ epicsShareFunc void epicsShareAPI threadOnceOsd (
     if ( ! win32ThreadInitOK ) {
         threadInit ();
         if ( ! win32ThreadInitOK ) {
-            return NULL;
+            return;
         }
     }