Outlook Add-in Error

There is a potential issue with Outlook and Symantec because of the way Outlook saves its add-in information. If the Symantec registry information changes, the user may receive the following error message upon opening Outlook:

  • The Add-in “Symantec Antivirus” cannot be loaded and has been disabled by Outlook.

There is a utility on the shares drive to fix this problem:

\\shares\SAV\System Support Users\Symantec SavPluginUtility

Instructions for use;

  1. Close Outlook
  2. Run application from \\shares location
  3. Open Outlook to see if it will load properly

Outlook stores cached registry entries for its add-in information in an extend.dat file located in the following directories:

XP: <User Directory>\Local Settings\Application Data\Microsoft\Outlook Vista/7: <User Directory>\AppData\Local\Microsoft\Outlook

When an Add-in changes, Outlook does not update its cached registry information to reflect the change, and the user receives this error message. If the utility fails to correct the problem you can delete this extend.dat file yourself and Outlook will recreate it with updated information.