Hi 123helpme,
You didn't happen to install the handwriting plug-in earlier, have you? This plug-in is known to cause problems like that when installed on Windows 98/ME or other versions that (sometimes) don't support it or when it has been installed incorrectly.
If you have, try to disable it from the Plugins section in the Preferences window by disabling it (removing the checkmark). Then reboot your computer and see if the problem is fixed.
If not, close down all Messenger related applications and remove the file MsnHandWriting.dll from your Messenger Plus!\Plugins directory, most likely the default C:\Program Files\Messenger Plus! 3\Plugins.
More information can be found at
http://shoutbox.menthix.net/showthread.php?tid=22276, it's the link Sunshine also gave. I suggest you read that, if you haven't done so.
If you do not remember installing the handwriting plug-in, it might be wise to try the solution mentioned above as well, as it may still apply to you. If this does not solve the problem, please give more detailed information (version numbers, did it happen out of the blue)
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