It might just mean your security settings are off.
Two reasons why you may not be able to install a Service Pack for Windows:
1. Security Settings are interfering. Windows cannot access the DCOM Server.
2. Windows is not Genuine.
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Now, please do the following first:
Please navigate to this webpage: http://support.microsoft.com/kb/313222 and see the section "Fix it for me" and click the Microsoft Fix-It button. This will download a fix utility to repair the security settings on your computer, due to damages of malware or other harmful system changes. Install the file after download.
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We Need to Diagnose a Possible Problem with WGAThis may be preventing you from installing that service pack.
- Please download MGADiag and save it to your desktop.
- Double click the icon on your desktop.
- Push
- Push
- Go to Start -> Run and type in "Notepad"
- Go to Edit -> Paste in notepad.
- x out all of the numbers and letters in the line beginning with "Windows Product Key:"
- Copy and paste that log here.