To remove Plus!
XP: Start > Control Panel > Add or Remove Programs.
Vista/7: Start > Control Panel > Programs & Features.
Find Messenger Plus! (only) and uninstall it. Start Windows Live Messenger again, and it it still doesn't work we know it's now Messenger Plus! causing the problem.
It could also be your internet connection. If you are wireless make sure the Ariel is connected in securely, and nothing is interfering. Is your connection going off too?
After doing that, check the quality of your phone line, by doing a test at
http://pingtest.net.
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