Many users are also reporting the same, one thought is that the user profile has become corrupt & the solution is to create a new one within cmd prompt under task manager. From the black screen press ctrl alt del to open task manager -> file -> run new task type "cmd.exe" without quotes, and check the admin privileges box. in cmd: type: net user /add [username] [password] username and password without [] press enter, then type: net localgroup administrators [username] /add logged into the new account you should be able to access the old account’s folders to transfer personal files over to the new account.