I just updated Windows Live Messenger to the latest (build 0206) and Plus! worked fine. Make sure that in the Windows Live Messenger directory (Usually C:\Program Files\Windows Live\Messenger) you have the file msimg32.dll (or something along those lines.) If you do uninstall Messenger Plus! and Windows Live Messenger and reinstall WLM then Plus!. the msimg32.dll is the Messenger Plus! loader.
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