Old Orders Disappearing

We're having a problem with one of our larger client ZC installs (1.3.8a) that I can't seem to find any help on anywhere on the internets:

Basically, it seems that after two months or so all old orders are getting deleted from the database. There are currently 265 rows in the orders table, but there should be more like 700.

We're running MZMT, Easy Populate, Image Handler 2, and the Sales Report mods, but I don't think any of those could be causing this problem. The site is hosted on a VPS with Network Solutions. My best guess right now is someone at the company deleting old orders, but they insist it's a technical error.

Any thoughts?

There is nothing built-in to Zen Cart that does any purging of orders on any particular scheduled basis.

I would suggest using the Admin Activity Log Viewer to see who's been doing what in your admin:
http://www.zen-cart.com/index.php?main_page=product_contrib_info&cPath=40_41&products_id=1030

Failing that, do a file-by-file comparison of files on your site vs a clean set of files, to see whether some script has been added that you didn't know about.

Check your hosting account for cron jobs whose purpose you don't recognize.

Check your database to see whether all the related orders tables have had all the related data removed, or is it just from the "orders" table? If it's been a dirty hacking out of data, then you'll see traces of the "missing" orders in the other tables -- ie: look at orders_id columns as a starting point.

Maybe change your database password if you think someone's deleting stuff via the database and not via your admin area.

Thanks so much for your quick reply.

Unfortunately there's a gap in our backups from when we ran them and when the admin activity was cleared, so we're missing the activity logs for the time when the old orders were supposedly cleared. The clearing does seem to be clean, because I can't find record of the old orders anywhere.

I think we're going with a human problem on this one. They always get in the way... :)