How to Uninstall a Disabled Outlook Add-On

Screenshot of the Outlook logo


"The add-on cannot be loaded and has been disabled by Outlook"

Outlook is firm about its disabling that add-in of which, it seems, you should rid yourself. You've tried, of course, uninstalling the application behind the Outlook extension — but to no avail.

Outlook isn't much help in letting you know where to uninstall the disabled add-on either or any add-in for that matter. Fortunately, it is but a short tour with a somewhat unexpected twist that takes you to the place where add-ons reside in Outlook. Trust it.

7 Steps to Uninstall a Disabled Outlook Add-On

To completely remove a plug-in from Outlook:

  1. Select Tools | Trust Center... from the menu in Outlook.
  2. Go to the Add-ons category.
  3. Select either COM Add-ins or Exchange Client Extensions, depending on the type of add-in you want to remove under Manage.​
    1. You can see each extension's type in the Type column.
  4. Click Go....
  5. If the add-on you want to remove is a COM add-in:
    1. Highlight the extension you want to delete.
    2. Click Remove.
  6. If the add-on you want to delete is an Exchange client extension:
    1. Make sure the add-in you want to remove is not checked in the list.
  7. Click OK.

Screen-by-Screen: Uninstalling a Disabled Outlook Add-On

  • Uninstalling the Disabled Add-On Screenshot Walkthrough

6 Steps if Outlook Can't Find The Disables Add-On is Somewhere?

If Outlook complains about an extension you can find in none of the add-in manager's lists, you can try deleting Outlook's add-in cache:

  1. Make sure Outlook is not running.
  2. Press Windows-R.
  3. Type "%localappdata%\Microsoft\Outlook" (not including the quotation marks).
    1. Using Windows 2000 or XP, use "%appdata%\Microsoft\Outlook" instead.
  4. Click OK.
  5. Highlight the "extend.dat" file.
  6. Press Del.

Screen-by-Screen: Finding the Disabled Outlook Add-On

If Nothing is Working

Should you run into more problems starting Outlook now than you had before, restore "extend.dat" from the trash. You can select Edit | Undo Delete right in the Explorer window in which you trashed the file.