On a Windows 2000 Professional workstation I am repeatedly offered a Windows Update. I've tried several times to install it. Each time it says it installs, but the icon keeps popping up telling me it needs to be. When I check the history of my updates it shows that it's been completed several times. When I go directly to the Update site it shows I've downloaded it but that it still needs to be installed...even though history shows it was. I've ran the Malicious Software Removal Tool, and it showed nothing. I've scanned the computer with spyware-fighting software and antivirus software. Tried installing the update in safemode, but Windows says I can't do it in safemode. The Update I'm having the issue with is "Security Update for "Microsoft XML Core Services 4.0 Service Pack 2 (KB936181)...Any ideas?