Recently I have bought a new PC and installed Windows Live Messenger 8. However, after signing in into my account, Windows Live Messenger is not responding at once, and the Windows prompt me to send an error report.

I have tried uninstall and reinstalling it, as well as trying MSN Messenger, but none work. Strange though, Yahoo Messenger still work. (I install Yahoo Messenger after several attempt to troubleshoot the problem.)

What can be the sources of errors.

A virus, malware or spyware infection can cause this

I have tried scanning my PC but still nothing works.

Try doing an XP repair:

http://www.geekstogo.com/forum/index.php?showtopic=138