I have an invoices download at http://www.officearticles.com/downloads/
It does just what you want. Perhaps you can steal the code from it. :)
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Anne Troy
www.OfficeArticles.com

"ritarowe" wrote in message
...
I have a purchase order spreasheet working with. I would like it to
automatically generate a unique identifier (PO number) upon opening the
file;
is this possible? or some formula to automatically pull in the next
sequential #?