Microsoft Outlook doesn't think the add-in is available.

[BCB:5:Third-party support:ECB]

If you receive an Outlook warning about an extension you can't find in the add-in manager's lists, delete Outlook's add-in cache.

1. Confirm that Microsoft Outlook isn't running.
2. Press the Windows key + R key.
3. Type %localappdata%\Microsoft\Outlook in the Run box.
4. Click OK.
5. Highlight and delete the extend.dat file.
6. Microsoft Outlook recreates the file when you restart it.

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