While it doesn't specifically list this issue, there's no reason you can't
use it as a guide to troubleshoot a registry that might be corrupted and
potentially is the source of the problem. You might also want to take a
look at the following Knowledge Base Article about recovering
http://support.microsoft.com/?scid=kb;en-us;Q307545 from a corrupted
registry:
Another possible source in your case may be McAffee which is a notorious
troublemaker. If you can't get to your desktop, try removing it in Safe
Mode and see if the problem goes away (IF McAffee is acting as your firewall
and you are on a broadband connection be sure to disconnect broadband modem
first and if you are on dialup, do not connect to the Internet until you've
installed a firewall). If the problem does go away, you'll need to discuss
the issue with McAffee tech support and/or check for any updates at the
website that might address the issue. Boot the system, start tapping F8,
when the menu appears, select Safe Mode and press Enter.