Hi,

There are several Microsoft Knowledge Base articles that document the exact error message you are receiving under different scenarios.  The resolution for almost all of the articles is
to search for and delete all instances of the "Frmcache.dat" file.  Outlook will rebuild this cache file the next time you launch it, and this will most likely resolve your problem.

To Delete the Frmcache.dat File

Close Outlook
Click Start , point to Find , and click Files or Folders .
Type "Frmcache.dat "in the Named box, and click Find Now .
Click to select the file and press DELETE to remove each instance of the file.
Restart Outlook

Regards,

Scott Atkins MCSE, MCSA
Partner Technical Lead - Outlook
Microsoft Technical Support
for Platforms and Business Applications
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