I am having an issue with internet explorer 7, it closes for no reason.....?

I have had internet explorer 7 for XP for about a year now. I hated it at first, but have grown to have a handshake understanding with it. Recently, for no reason I can ascern, it shuts down completely. Blink and it is gone. I have looked for updates, and have found none. Anyone know what is causing this, it is VERY annoying!