I had a system today with 8000ffff error when trying to run Windows Updates. I found tons of posts clarifying how to get past this on Vista, but it didn’t apply to Windows 7.
Here is what I did that worked:
Run a command prompt as an administrator (Start: type ‘cmd': right click on the Command Prompt option, select “Run as Administrator”
Type the following commands:
net localgroup administrators localservice /add
net localgroup administrators networkservice /add
Viola. Issue resolved. I’ve had one other system recently that couldn’t get an IP address with a network card (wired or wireless) and couldn’t start the Network related services. Same problem. I hope this helps someone out there!