Hello Laura:

Another approach is to try and narrow the search a little.

First, did anything change just before the problems started? New computer? Old computer showing signs of failure? One computer being used much more than previously? Power problems? UPS problems? Computers moved recently (leading to cable problems)? New user? Changes made to the server? New hub/router? Virus infection?

Next, since both occurences were related to OE and AR data tables, start with the computers that do a lot of work in those 2 modules. Put the AP clerk's computer at the bottom of the list. If possible take one of the suspect computers out of service for several days (though admittedly this isn't always an accurate test with intermittent problems).

If your business is such that you can get everyone out of Adagio at lunch, do a Backup and Data Integrity Check and again at the end of the day. If there is a problem again this will allow you to narrow the time-frame and to restore from backup without losing too much work.