|Make sure you back up before anything is tried.|
How to back up and to restore Outlook Express data
An Outlook Express basic repair kit
I also would recommend Thunderbird
Just some things to try. Good luck
"Don't hit at all if you can help it; don't hit a man if you can possibly avoid it; but if you do hit him, put him to sleep."
Theodore Roosevelt New York City, February 17, 1899