I see that the "Log me in automatically" check box had become unchecked. So I checked it again to see if it helps.
Regarding losing messages when you are not logged in properly, that was the reason I switched ot Firefox for a browser. It does a much better job of "remembering" what you typed when you have to back up. Sometimes when I am posting to a Wiki I would get a timed out message (especially with SuWiki which is unbelievably slow and subject to timeouts). With IE, the message would be lost. With Firefox, I could back up, have the whole message there, and submit it again.