Just after upgrading to Windows 10, many users stopped at a black screen instead of Windows 10 desktop.
If you are one of users who just upgraded to Windows 10 and now is sitting at a black screen for too long time here is how you can fix the problem.
How to Fix Black Screen
Okay you just upgraded and you are tired looking at the black screen, restarts also didn’t help. First make sure that you don’t have any other monitor connected to the computer.
If you have an integrated Intel graphics controller with a discreet CPU on it, Windows thinks that you are using one another monitor. So the signal goes not to your monitor but to the another one that actually doesn’t exist.
Then press enter and you should login to your desktop, which still can be black. So after hitting enter key, wait about 30 seconds and press Windows Key + P, then down arrows 2 times and enter. You are blind, but this will get you to the menu where you will select to Duplicate your screen.
Below is a Microsoft Knoledge Base
“The lock screen in Windows 10 Technical Preview Build 10061 might appear as a black screen with a mouse cursor
When you sign out of Windows 10 Technical Preview Build 10061 and return to the lock screen, you might see only a black screen with a responsive mouse cursor. Pressing the Alt+Tab keys or the Ctrl+Alt+Del keys has no visible effect.
If you are experiencing this issue, follow these steps to sign into Windows:
At the black screen, press the Ctrl key once on an attached physical keyboard. (You won’t see any visible change, but pressing the Ctrl key will place the cursor in the password box that you’re currently not able to see.)
Now type the password of the user that just signed out and press Enter.This will sign you back into Windows and the desktop will appear.
If you failed to sign in because you mistyped the password, press Enter once more. Then retype the password and press Enter.” …
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