Windows Update Fails
This KB article from Microsoft might be useful with Windows failed to run an Update:
Method 1: Register the Wups2.dll file in Windows
To register the Wups2.dll file in Windows, follow these steps:
1. Stop the Automatic Updates service. To do this, follow these steps:
a. Click Start, click Run, type cmd, and then click OK.
b. At the command prompt, type the following command, and then press ENTER:
net stop wuauserv
2. Register the Wups2.dll file. To do this, follow these steps:
a. At the command prompt, type the following command, and then press ENTER:
regsvr32 %windir%\system32\wups2.dll
Note For a computer that is running Windows XP Professional x64 Edition, type the following command, and then press ENTER:
regsvr32 %windir%\syswow64\wups2.dll
b. Click OK on each verification message that you receive.
3. Start the Automatic Updates service. To do this, type the following command at the command prompt, and then press ENTER:
net start wuauserv
4. Exit the command prompt. To do this type exit, and then press ENTER.