MSN Messenger Keeps Quiting !!

I installed MSN Messenger for Mac a week ago so i could chat to my friend who is on a windows based machine. Everything was fine untill two days ago when i sign in and went to click on my friends icon to chat to him, it would just quit unexpectedly.

Any ideas ??

I'd start by quitting MSM and moving it's .plist (it's preference) to your desktop, then running it to see if it crashes.
They are located in ~/Library/Preferences/
(The tilde (~) means 'your home directory') and they are called:
MSN Messenger Preferences
MSN Messenger.plist

Move them to the desktop. MSNM will recreate them when you run it. If the originals are corrupted in some way, then moving them and having the app recreate them will alleviate the problem. If you problem is gone, go ahead and trash them. If it's still there, you can put them back where you found them.

I would recommend using Adium for to chat with your MSN friends.

Like Schweb said, Adium works flawlessly and bundles all of the major messenger services within one all encompassing package.