During end of the year posting. posted using batch process worked correctly. ran reports "OK". renewed lic. via disk form DBA ran an end of month report for Oct some of the prevously posted batch file was now split between two different companies and we have not using old second company at all for year but never deleted company-- the carry over balance are incorrect --new balance which were "OK" at "zero" new balance now have a balance --I know we can correct posting error by using adjustment-to retained earnings account. Is there any other hidden problems I need to look for. My question is how did this happen and can I keep it from happening again.  ???