My PC is running Win XP, SP3, IE7, Outlook express 6

Just the other day, when I clicked on the Outlookexpress icon, the
Outlook Express^ splash screen pops up and then will not go any
further. My IE& web browser works, as well as everything else on the
computer. I've tried rebooting, virus scans. Alot of the online forums
suggest reinstalling OE6, but Windows will not let me. I can't even
get into OE to check folders and things.
Any sugestions would be greatly appreciated.