Are you using any programs such as Smiley Central or Messenger Plus!? If so try and uninstall them and see if MSN Messenger functions properly without it. Also if you do have Messenger Plus! installed have you installed any Plugins if so I might consider removing them and trying. A system restore might remove the registry entries for the plugin and if they are not coded properly can potentially cause MSN Messenger to crash.
You can also try to completly uninstall MSN Messenger and reinstall the latest build from
http://messenger.msn.com and see if this works.
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