diff --git a/obpar.c b/obpar.c
index c89ef725..d9e40ccb 100644
--- a/obpar.c
+++ b/obpar.c
@@ -176,7 +176,9 @@ int ObParSet(ObPar * self, char *obname, char *name, float fVal,
 
   /* are we running? */
   if(DevExecLevelRunning(pServ->pExecutor, RUNDRIVE)){
-    snprintf(pBueffel,sizeof(pBueffel)-1, "ERROR: Cannot change parameter while running");
+    snprintf(pBueffel,sizeof(pBueffel)-1,
+        "ERROR: Cannot change %s.%s parameter while running",
+            obname, name);
     SCWrite(pCon, pBueffel, eError);
     return 0;
   }