Peachtree/Sage 50 used to have a bug that caused customer IDs to stop working once they reached a little over 10,000 transactions. I don't remember exactly when the problem was fixed, but I think it was later than 2009. If this is a really big customer, your only option may be to start a new customer ID (or upgrade the current version).

Thanks for your kindful answer.

Hi Polymer, 

Steve is correct.  I too remember that as being an issue.  There was a hidden limit.

As Windows 7 is expiring in January of 2020 and Peachtree 2009 will not work on Windows 10, you might want to consider an upgrade to Sage 50 2019.  

 Steve and I both sell Sage 50 perpetual licenses.   Please feel free to look our way if you  do choose to upgrade your program. 

Shirley Byard, Owner of Best Business Strategies 304-233-2612  [email protected]