Let me comment that your subject title is slightly off. If there were empty, I'd say you have an issue like http://reviews.cnet.com/5208-6141-0.html?forumID=8&threadID=18878&start=0
But you don't. It's more likely you installing IE/OE 6.0 and need to look under Tools, Options, Security to set it as you see fit.
Worth noting is that if you are PREVIEWING email or opening email from people you don't know, there is something going around that causes email to appear blank. The fix is hairy as you can read at http://reviews.cnet.com/5208-6141-0.html?forumID=8&threadID=18878&start=0
attachments come through but won't open. when I click on the paper clip the save attachment option is grayed. I can't open other attachments that were there before either. any one have a clue ?? this just started all the sudden..