1) Disable all the Messenger Plus! scripts you might have:
Plus! > Preferences > General > Scripts > untick all scripts > press Apply or OK...
It is important that you don't get any error messages when you do that.
2) Log out and restart Messenger and see if the problem still occurs
If it doesn't occur anymore, there is a faulty script which lets Messenger crash.
If it still occurs:
3) Uninstall Messenger Plus!.
Windows Control Panel > Add/Remove Programs > Uninstall Messenger Plus! Live
If it doesn't occur anymore, there is a bug in Messenger Plus! Live.
If it still occurs, it isn't the fault of Messenger Plus! Live, so:
4) Do you have any other addons for Messenger (SmileyCentral, StuffPlug, etc...)? or any patches (MessPatch, A-Patch, etc...)? If so, uninstall them all.
If it doesn't occur anymore, then one of the patches or addons caused the crashed.
If it still occurs, it might be a bug in Messenger or in some of the user content you have (Winks, etc...):
5) Try a total clean re-install of Messenger. See:
CookieRevised's reply to Windows Live Messenger BIG PROBLEM!
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