“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.” Microsoft says. If you still having the same issue after installing the update, Microsoft recommends the following instructions:
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.
The new update, should download and install automatically, but if you can’t wait, you can open the Setting apps, navigate to Update & recovery, then go to Windows Update, and check for new updates. Source Microsoft All content on this site is provided with no warranties, express or implied. Use any information at your own risk. Always backup of your device and files before making any changes. Privacy policy info.
