It's not Messenger Plus!'s fault that you can't sign in into MSN Messenger. Messenger Plus! doesn't alter in anyway the way MSN Messenger connects to the MSN servers...
I'm sorry this happend, but chances are that if you didn't install Messenger Plus! that you still couldn't sign in. This is pure a coincidence that it happend the same time...
It would help though, if you gave the exact error message (including the errornumber) that you get from MSN Messenger. Also include the exact and full version number of MSN Messenger (something like 6.x.xxxx (fill in the x's) you'll find it in "
ToolsHelp > About") and the full and exact version number of Messenger Plus! (2.xx.xx, you'll find it in "Plus > About").
EDIT: thanks, jmccarroll
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