Not every site is set up in such a way that IE recognises the boxes you fill in as containing a user ID and password. If you didn't get the message asking you if IE should remember this password, then I would guess this to be the case here. You could try using Firefox and see if the built in password manager does work on your page, but if that fails also then there's not much you can do. Since the problem resides in the page coding itself you could only ask your email provider about it.