Although it's labelled as for mail stuck in the Outbox, it also works in
other folders. If you don't know whether to use the 32-bit version or
the 64-bit version, try the 32-bit version first. Certain common
antivirus programs, such as most of those from Norton or McAfee,
tend to cause these and other problems in Windows Mail, although
seldom immediately, so if you have such a program, remember
where to find the fix and hope it will work again. A recent version
of the Trend antivirus program also causes assorted problems in
This will help show you how to fix the stuck undeletable email message problem in Windows Mail.
The KB941090 update will just fix the problem for now. You must stop the cause to prevent it from happening again. Read the "First" section in this tutorial about antivirus and anti-spyware/adware programs to help prevent this from happening again, then install the KB941090 Microsoft Update in the "Second" section to fix the stuck message problem.