Strange Email from Microsoft Corporation Intenet Security Department

From: Mark (markcondit_at_cox.net)
Date: 05/13/03 

Date: Mon, 12 May 2003 19:52:03 -0700

I keep recieving an email supposedly from Microsoft tell
me to run an attached program update. The email is
from "Microsoft Corporation Intenet Security Department".
This is too hinky to be real. Is there such a department?
Does anyone know what this is? Thanks