It may have been lack of training, or situational awareness that caused this mess.  Our office manager didn't notice/or react and now two years later we have a bunch of open PO receipts.

We chased down the issue to the invoices from the Vendors being entered directly into AP invoices, thereby not completing the receipts.  If we complete the receipts then we would have doubled their value in the AP and IC accounts.  

If we zero them out, it will take the value out of IC.  Luckily it isn't that many.  What if we invoice them, and then do a refund of the AP invoice and a fake payment on the PO invoice?  Or just make a fake payment on the PO invoice and refund that?

Any other ideas?  Also some of these invoices were paid via credit card, I think we found a good way to deal with those going forward.