Duplicate Output Destination

[rwn]

I'm trying to create an append query to add routing sequence steps for new routings. When I run the query it state duplicate output destination, I understand the message for it is indicating that some part routings already have a sequence 40. I need to have the append query disregard those part routings and only append the query to part routings without a sequence 40. Thank you in advance!

The query is as below:
INSERT INTO [Part Routing] ( PRTNUM_12, OPRSEQ_12, WRKCTR_12, OPRDES_12 )
SELECT [Part Routing].PRTNUM_12, "60" AS Expr1, "LAB" AS Expr2, "LAB" AS Expr3
FROM [Part Routing]
WHERE ((([Part Routing].PRTNUM_12)="000001") AND (([Part Routing].OPRSEQ_12)="40"));