Non-existent fax extension causes Outlook error

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My clean installation of Windows Vista and Office 2007 has been presenting me with a strange error on the first time that I reply to an e-mail in Outlook:

Microsoft Office Outlook

The Add-in “FaxExtension” (C:\Windows\System32\fxsext32.dll) cannot be loaded and has been disabled by Outlook. Please contact the Add-in manufacturer for an update. If no update is available, please uninstall the Add-in.

After clicking OK, everything is fine until the next time I open Outlook and reply to a message. It’s all a bit odd, because I don’t have a fax extension installed. Then I found a newsgroup post which commented that sometimes deleting the FaxExtension key from HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Exchange\Client\Extensions will prevent this error from occuring.

I checked the registry and sure enough, there was the key, with a value of 4.0;C:\\Windows\\System32\\fxsext32.dll;1;00000100000000″.

I shut down Outlook, removed the offending key, restarted Outlook and haven’t seen the message since. Guess that’s a bug then.