I have been fighting with this for a couple of days now. My Windows 7 Home Premium PC won't update to SP1. I tried both the stand-alone SP1 installer and the normal Windows Update route without any success. Windows Update downloads SP1 but fails soon after starting the installation. The stand-alone SP1 executable fails too. Both produce the same error 8004100E. I can't find anything meaningful about that error number through "Googles". 
I tried stopping the Windows Update service and cleaning out the \Windows\SoftwareDistribution folder with no luck. It only lets Windows Update download SP1 again with the same failure during installation.
This is a genuine copy of Windows that came pre-installed on a Dell PC.
Any suggestions would be appreciated.
I tried stopping the Windows Update service and cleaning out the \Windows\SoftwareDistribution folder with no luck. It only lets Windows Update download SP1 again with the same failure during installation.
This is a genuine copy of Windows that came pre-installed on a Dell PC.
Any suggestions would be appreciated.