hi there. One of the updates in Windows Update keeps failing. It says it's an important one too. I'm getting error code 80070643 When I go to this http://support.microsoft.com/kb/903772 website to FAQ the problem, I get to method 2, stage 2. "2. Insert the Office 2003 CD in the CD drive. " I've got no idea what this disc is. Why does it assume I've got it??