some interesting info i found :
This issue has been fixed in System Software 15.002.51.000 expected to be released mid/late April, 2010.
The Image Overwrite feature is now working correctly as follows:
With STANDARD image overwrite, the Fax Phonebook does NOT get overwritten.
With FULL image overwrite, the fax phonebook DOES get overwritten.
In most cases, the user should choose STANDARD when performing a Manual or Scheduled Image Overwrite. If they choose FULL overwrite, the jobs and folders in the "Reprint Saved Jobs "feature, the Fax Dial Directory (Fax Phonebook), and the Fax Mailbox contents will be overwritten..
We have a 4250 that keeps dumping the numbers entered into the addressbook overnight. I've tried a firmware update with no success. Any ideas on what might be causing it?
The printer is also set to do an ondemand image overwrite every night. Might that have something to do with it?