I instaled Mesenger but I haven't log in?

I have instaled Yahoo Mesenger but I can't log in. Also I can't log in MSN Explorer and I can't install Windows Messenger.

I instaled Mesenger but I haven't log in?
Let me tell you that this is not a problem. I can tell you from experience that you will benefit from this. Forget these messengers before they take over your life. Learn to read. I mean entire BOOKS. If you want to talk to someone, leave your home and find a real person an speak to the face to face. Think about this carefully, and you'll see that I am right.
Reply:Do you have a yahoo id? Just click on the YM Icon and login with your Yahoo ID.
Reply:Give it some time check your un and password