I accidentally entered the wrong vendor on a PO.  One of my helpers received in the Purchase Order, created an invoice in AP-C.  but when she went to pick and pay she didnt find the vendor invoice.  That is when she let me know that I had used the wrong vendor.
 
I knew we needed to reverse things in the exact same order.  One thing I want to make sure my receipts are correct in IN-A.
 
1. Reversing AP-C is easy as long as you have the correct invoice number and date.
2. Re-open in PO-D   You would think the 2nd reversal step would be reverse PO-C but it is not.  
3. Reverse PO-C, making sure you select display all received lines.    Here is what is odd.  Before you reverse it you would think that PO-C reflect rec'd quantities but it doesn't!   It shows zero as received  before I reversed it. So i took a gamble and entered a negative 30 in the quantity and proceeded to reverse.  
4.  I ran PO-I-E to confirm and happily i got a report that showed  (+30)  and (-30) for a quantity of zero received.   I was worried that I would not  have a qty of zero but of  minus 30 given what I had first seen in  PO-C
5.  I was not able to go to the original PO and select the correct vendor code.      
 
 
Before this i did not know that I had to re=open in PO-D before I could reverse.  Not do i understand why PO-C did not show a qty of 30 rec'd in.   I would think that if i reopen a PO in PO-D that PO-C would reflect the last receipt.
Thanks