This hasn't got anything to do with Messenger Plus!.
Messenger Plus! and MSN Messenger are two seperate programs; you still use MSN Messenger to chat and talk to contacts as you always would.
Messenger Plus! only adds extra features to MSN Messenger. Hence Messenger Plus! is an addon for MSN Messenger; it does not replace it...
Thus, this should have mostlikely been posted in "Windows/MSN Messenger" subforum...
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For the problem; I see that you're using some sort of Windows skin. Do you use any styling programs for that? If so, that can be the cause...
Also, do you use some special driver or program that came with your graphics card to beef up the look of windows (eg: transparency)? That can be the cause as well...
Also, I read that it is a new kind of graphics driver. New drivers often has problems...
Either way, this problem is either because you used one of the above or because of a bug in MSN Messenger (which I doubt), but certainly not because of Messenger Plus! (which you can test by not running Messenger Plus!).
If it is the latter (bug in MSN Messenger), I'd suggest you to write a detailed report to MSN Messenger itself:
http://messenger.msn.com/help/contactus.aspx
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But as said, I even doubt this is a bug in MSN Messenger. I have a strong suspicion this is due to your Windows skinning program you use. To test this, use the default Windows skin and don't use the skinning program you're using atm...
After that, and if it is still there, try to switch off all the fancy stuff you might have selected in your graphics driver. If it is solved with that, then it was one of your settings of your graphics driver properties.
If it is still there, then try to switch to the standard VGA driver and test it again. If it is fixed with that, then again it was your graphics driver which was seriously buggy.
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