What kind of crazy do you speak of? Is it acting on its own? Or is it giving an error such as username/password incorrect? Before digging too deep into a possible issue with IE or Outlook, there are a couple of things that I'd recommend to try and check out first.
Most ISPs allow you to check the mail you usually view in Outlook through their website...Useful for those away from home or that don't want to use an email client program. See if this is an option, log in through the site, read your mail and delete everything that isn't necessary. This will sometimes get things going again via Outlook.
Be sure that your email account settings in Outlook are correct. It's always possible that something in there needs corrected. Why? The dog or the kids may have accidentally changed something. ISPs and email services, not often, but every once in a while, will change stuff on their end. @yaya.com may now be @dada.net. Incoming and outgoing mail server addresses occasionally change also. Most, if not all, ISPs should have the correct info that you need on their website. If not, they should be able to give this to you over the phone.
Be sure you have the latest updates via Windows Update or Microsoft Update.
If all else fails, there isn't a way to uninstall/reinstall Outlook Express under XP, but you can use the system file checker to make sure everything is in check. This shouldn't be used as a fix all, but only if necessary, and I've seen it fix Outlook Express issues a few times. Click Start, then Run, type 'sfc /scannow' (no quotes) and then click OK. Follow any prompts that there may be such as Yes to continue or Ok to replace a bad/corrupt file.
Hope that works for you.
