Original post : 0x000000EF (CRITICAL PROCESS DIED) - Fix for Windows.
Your PC ran into a problem and needs to restart. We're just collecting some error info, and then we'll restart for you. (0% complete) If you'd like to know more, you can search online for the error: CRITICAL_PROCESS_DIED
msconfig
devmgmt.msc
devices and printers
C:\
sfc /scannow /offbootdir=D:\ /offwindir=D:\Windows\
Reinstalling Windows might cause your personal files to be deleted. You can use Easy Recovery Essentials' Browse/Backup Files feature to backup your files before doing so, if you can't boot into Windows.