Do you have three icons in the bottom right corner of your Login screen? Right click the one on the right (see the image below) and select Update and restart. The login screen will reappear. Enter your password or pin number and with luck you will be able to access your computer.
I can't believe I wasted over 1h restarting 20 times and trying every possible combination of keys and clicks to find out ultimately that all I had to do is right-click on the bottom right button.
Thanks for the solution. I was 3 mins away from reinstalling windows.
Thanks Titus ... will try this next time. After trying various suggestions, none of which worked for me, I disabled the sleep mode when the lid is closed. Haven't had any problems since but would prefer to re-enable sleep mode, so try this solution.