prøv dette her,det skulle virke:How to fix "Service Pack 1 Setup Error The product key used to install Windows is invalid..."
Log in as the local Administrator
Click Start > Run > and type in Regedit
Browse to HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\wpaevents
Double-click OOBETimer
Remove the 'ca' part from the value. (Changing or deleting any of the binary values will accomplish the same effect)
Click OK and close regedit
Click Start > Run and type in: "%systemroot%\system32\oobe\msoobe.exe /a"
Choose the 2nd option (phone activation)
Click Change Product Key (at the bottom)
Enter your valid Corporate Product Key:
Generate one yourself with xpkey.exe (also found this p2p share)
or use
FH4HD-4JVJP-6G4GD-WWBGD-89JVH (then again, m$ might include this one in sp2 if you all start using it... )
Press Update and close the window
Restart your computer
Verify the change
After the workstation restarts, click Start > Run
Type in: "%systemroot%\system32\oobe\msoobe.exe /a"
Make sure the dialog box says 'your copy of windows is already activated'
Now start the service pack again, worx fine.