Outlook Express not showing message in preview pane
Try this fix first:
Click Start
Click Run
Type in regsvr32 inetcomm.dll
Click OK, or Go, whichever your system has.
If this doesn't work, check for:
Old versions of the Pennswoods Internet Accelerator (a.k.a. "Slipstream"). Make sure you're running the latest version, which can be found here
Your antivirus program may be scanning email. This always seems to cause issues at some point, and should be disabled, since your antivirus software should discover the virus regardless.