Microsoft has rolled out a small update (KB3055415) for Windows 10 build 10061 addressing a lock screen bug, which might appear as a black screen with a mouse cursor. Microsoft has provided a few workarounds along with a fix. Build 10061 was recently released to Windows Insider Program participants in the fast ring.
"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 explains. For those of you who are still experiencing this issue and are unable to log into Windows, try one of these options:
- 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.
Once you are logged in, head over to Windows Update and snag this update. Let us know if you are having this issue and if the update resolves it.