I was totally stuck with you in the same problem. None of the info from QB helped at all. I tried for a couple hours to figure this out. Finally, I tried adding the refund check to just Accounts Payable, from the vendor. THAT WORKED! I couldn't use the vendor's AP account specifically. in the check deposit. I then found the "bill" in the paybill's section and could add the credit that way. They make it sound like you need to add it to the AP account you are receiving it from, when it is actually just the overall AP account you need to use. PHEW. Hope this makes sense. That was WAY more complicated than it needs to be.
