Virus Alert - Bogus messages that seem to be from Microsoft
As of September, 2003, there's a breed of virus that sends email or newsgroup messages that look exactly like an HTML message from Microsoft urging you to run an attached security patch.
THESE ARE NOT FROM MICROSOFT -- DO NOT OPEN THEM -- THEY ARE VIRUSES
Microsoft NEVER sends security updates by mail or newsgroup messages.
If you've subscribed to an alert service, MS may send email about new updates, but it won't send the update as an email attachment.
Remember: If it has an attachment, it's not from Microsoft. Don't run it.
Here it is, quoted straight from Microsoft:
Note: www.microsoft.com/technet/security and www.microsoft.com/security are authoritative in all matters concerning Microsoft Security Bulletins! ANY e-mail, web board or newsgroup posting (including this one) should be verified by visiting these sites for official information. Microsoft never sends security or other updates as attachments. These updates must be downloaded from the microsoft.com download center or Windows Update. See the individual bulletins for details. Because some malicious messages attempt to masquerade as official Microsoft security notices, it is recommended that you physically type the URLs into your web browser and not click on the hyperlinks provided.