Reseting the Activation Trial:
In this example: Your activation period has expired, (past 30 days) and you need to get to Normal mode again.
1. Turn On your PC
2. Press F8 repeatedly and go to Safe Mode
3. Logon as per normal
(note: Administrator password is usually blank, but hopefully you know your password)
4. Allow the Desktop to fully load (answering "Yes" to continue into Safe Mode)
(note: This is just a long way of saying go to Safe Mode)
5. Click on Start - Run
6. Type in exactly: rundll32.exe syssetup,SetupOobeBnk (and click OK)
(note: one space, after "rundll32.exe " also the Oo are two letter o's in "oobe"; capitals and comma are important)
7. Wait a couple of seconds (although you will Not see any change)
8. Restart your PC normally (Start - Shutdown - Restart - Ok)
9. You are now able to go to Normal Mode again (For another 30 days !!!)
10. Do whatever you like, you're back to Normal.
This fixed it for me but took me a long time to find this and get it going, hopefully it works for you to.