Hi Rebecca:

I think your only answer is to tell the client to [Tab] from the Customer field to the "Adjustment #" field and start typing.

But your question does raise an interesting issue. I never noticed before but Receivables doesn't verify the document number for uniqueness until the batch is posted (applies to Invoice and Adjustment entry). In the Receipts window, the "Check" field is verified and a duplicate flagged but the user can proceed. In all 3 situations, posting will fail.

Payables verifies and prevents duplicate invoice numbers immediately upon entry.

I know there is a reason behind design decisions but immediate verification would make sense and would cause less frustration for users like Rebecca's client.