Why go to all this trouble???  If it is simply an incorrect price on the PO, enter the correct price in AP-C and everything will be updated properly.  Price change entered in AP-C will pass the price change through to the inventory.

We use the following procedure for returning previously received items back to the suppller:
 
If the PO is closed, one would need to re-open the PO in PO-D, VIEW PO RECEIVERS menu.  Then edit the purchase order in PO-A, ENTER PURCHASE ORDERS to add a new line item for the negative quantity (you wish to unreceive).
 
Receive the negative qty in PO-C, RECEIVE PURCHASE ORDERS, and have accounting process the credit (as a RMA credit voucher)  in AP-C and RE-CLOSE the purchase order.
 
NOTE: If one does not re-close the purchase order, PO-I-F, RECEIVED/NOT INVOICED REPORT, will show items previously received and processed in AP-C as open items on this purchase order.  For this reason, some may prefer to create a new purchase order, but the supplier usually references the original PO number in the RMA.
 

Before you re-close the purchase order in PO-K, I just make sure everything has been processed in AP-C.
 
When you re-close the purchase order in PO-K it may prompt you that there are unbilled dollars open on this po (which may not be accurate) so I like to be sure that everything is processed.
 
YES, my experience has been that the subject purchase order is then removed from the PO-I-F report after re-closing.
 
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