Michael:
Isn't there a syntax issue here?
You are asking " ... NoSerial_No NOT IN (SELECT StockNo_No FROM StockNo)" where the list (...) does not contain the field you are wanting to filter on.
Try: NoSerial_No NOT IN (SELECT NoSerial_No FROM StockNo)
Hope that helps
Godfrey
Godfrey Nicholson
Ofek Technologies Ltd
Auckland
New Zealand