This was figured out by me to help you all who
have problems being interrupted in the middle
of something or game by a messenger pop up.
DO NOT waste your time downloading software
to get rid of this problem.
Here is a fix for you NT/XP folks...
1. Click on My Computer and open the control panel.
2. Open the Performance and Maintenance or
3. Double-click on Services, and scroll down to Messenger.
4. Double-click Messenger and click the Stop button
which will stop the service.
5. Change the startup type to Disable.....no more
Messenger popups. This NOT MSN Instant Message service
called Windows Messenger but this IS a component part of
Windows XP only for Network Administrators to send
broadcast messages to network users.