Whenever I try to log onto MSN from this computer, I get the message that 'my user name doesn't excist or my password is wrong'. I find this odd, because I have no trouble using the messenger from other computers. I've speculated that it was the Firewall causing these problems, but disabling it didn't work either. Suggestions?

Is this Windows Messenger or MSN Messenger? Also, is windows firewall turned on?

It's the windows messenger. Or so it is called. I was unaware there was a difference between the two. And yes, the firewall was turned off.

Try using www.e-messenger.net
it's not a great system, but it's much better than nothing, as I don't have a proper soloution to your problem.
You could try downloading MSN messenger, from here for a better alternative.

Windows Messenger is known to have problems. My advice would be get yourself a copy of messenger 6 (or you can try the 7 beta.)Unfortunately M$ don't allow older versions anymore which is a pity.

E-messenger kinda sucks really, it has the annoying refresh thing. If you do want to try a web based version of msn, try this

I think your best bet would be to download messenger 6.2 and scrap windows messenger.

That's pretty cool, Web Messenger I mean, I've never seen that version before, it's a lot better than e-messenger.