For starters use the latest versions of Messenger and Messnger Plus!, in your case this is
MSN Messenger 7.5.0324 and
Messenger Plus! 3.63.148...
Before installing anything make absolutely sure you have no plugins for Messenger Plus!. If you do, remove them first.
And then, before installing anything, remove both MSN Messenger and Messenger Plus! in the proper way:
1) Go to your Windows Start menu
2) Go to your Configuartion Panel
3) Select Add/Remove Programs
4) In that list you'll find both "MSN Messenger" and "Messenger Plus!", remove them both.
Then you download the latest versions of MSN Messenger and Messenger Plus! and you install them one by one, reboot when you're done.
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Then for the cause of the error:
read this post in that very same thread you've linked to and posted in before:
http://shoutbox.menthix.net/showthread.php?tid=51...d=557625#pid557625
and
http://shoutbox.menthix.net/showthread.php?tid=51...d=565589#pid565589
The solution is to disable the "Buffer Overflow" detection feature of McAfee's VirusScan Enterprise 8.0 as stated in one of the posts in the thread linked to in the above posts.
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