[ok, I did not understand at 100% but I think what u trying to say is that while running MSN Messenger 7.0, you tried to log-in and it said "service is unavailable". Then u installed Msn Messenger 8.0 beta (which btw is leaked so then illegal to use except if you are a beta tester) and it did not work. If this is the problem you're having, I'd suggest following these steps]
1- Uninstall WLM 8.0 by going to :
Control Panel ---- Add/Remove Programs ---- Messenger Beta
2- Re-download/Re-Install Msn Messenger 7.0 ( or 7.5 )
http://messenger.msn.com
Download/Install
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Now try to log-in, if you're still having problems, make sure that :
1- You have no active Firewall / Antivirus
2- You're connection is working properly
If you have verificated these, then maybe the MSN Messenger server you're on is down (usually it goes away after a MAXIMUM of 24 hours), you can switch Msn Messenger server using this little program :
http://www.msgstuff.com/downloads/pafiledb.php?action=file&id=88
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Hope it helps
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