I installed a fresh Windows 8 (Pro) on my PC and when it gets to the log in screen, it just shuts down?
How can i fix this?
I have done some poking around and it seems there could be an issue with Hybrid Shutdown. This is along shot but this is how you can disable it.
You might need to do that in safe mode if you can get in that way... Buuut they changed something with safe mode... Hmm? Read this
If you cant get into safe mode try and do a normal full shutdown from power button on login screen? or just pull the power plug(I know-but that wont do the hybrid shut down thing and possibly let you in once to change the setting!)