First would recommend running Sage Data Integrity on IC and PO. Next turn on RvSpy (write to file) and duplicate the error. We would be glad to review the RvSpy log.   [email protected] 

RvSpy helped me to track down the two issues that were causing the stalling. thank you!

What were the issues can you remember?
I have the same situation where on one RDS server this happens but on all the other servers at the client, the day end is fine.
I've re-run regacc.
It's just a workstation install on each RDS (which works perfectly well otherwise) and it was working (although now we can't be sure if day end was run on this particularly machine previously but it is one of the oldest RDS servers on their farm so it most likely has been working).

The user did not remember the steps they did that caused the issues.  However, we use APS payment solutions and their add on module to process credit card payments. The users remembers trying to credit the customer on an invoice that has been processed by APS Invoice module for credit cards.  So, perhaps an issue with that.

We also noticed that the credit sequence had been messed up and the next credit number had been set to something that was used years ago.  

I created a sample new company, copied all the data over. Checked the DB for any references to the credit header number.  Only found it in the OECRDH table.  So deleted the line.  We fixed the credit sequence number and tested a little with the sample company adding new credits, invoices, etc.  Then we tested end of day.  All worked fine. So, we repeated in live company.  

Its been 2 months.  All seems fine!

The user did not remember the steps they did that caused the issues.  However, we use APS payment solutions and their add on module to process credit card payments. The users remembers trying to credit the customer on an invoice that has been processed by APS Invoice module for credit cards.  So, perhaps an issue with that.

We also noticed that the credit sequence had been messed up and the next credit number had been set to something that was used years ago.  

I created a sample new company, copied all the data over. Checked the DB for any references to the credit header number.  Only found it in the OECRDH table.  So deleted the line.  We fixed the credit sequence number and tested a little with the sample company adding new credits, invoices, etc.  Then we tested end of day.  All worked fine. So, we repeated in live company.  

Its been 2 months.  All seems fine!