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Addins in Windows Live Messenger
http://www.vistaarticles.com/articles/56/1/Addins-in-Windows-Live-Messenger
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Published on 08/20/2006
 
Addins in Windows Live Messenger

Addins in Windows Live Messenger

Copy and Paste the following into a .reg file and import it.

REGEDIT4

[HKEY_CURRENT_USER\Software\Microsoft\MSNMessenger]

"AddInFeatureEnabled"=dword:00000001

Once you import it, restart Windows Live Messenger and under Options you will have a new list item for Add-ins.