I have a Samsung Ativ Tab 3 tablet, which has been running Windows 8.1 flawlessly forever. Yesterday I ran windows update (it had been a couple of months since last updating) and received a number of updates. While applying the updates, I got the Shutting
Down message, and the tablet shut down.
Now, every time I start it up, it lasts through the login, and just as it gets to the desktop, it shuts down.
I can boot into Safe Mode without issue.
So last night, I did a full wipe and reload - back to Windows 8. I installed Windows 8, no problems. Added all the Windows 8 updates, no problems. Upgraded to Windows 8.1 through the store, no problems. Applied all the Windows 8.1 updates.... and, boom, I have the shut down behavior again.
If I move back to a restore point, I can log in again.
But I am unable to determine which update is causing this behavior, or why this is happening.
I am not the only one having this problem... https://www.reddit.com/r/windows8/comments/4u2k55/windows_81_update_causing_shut_down_on_log_in/