Windows 10: Why do I have a small duplicate screen

After an upgrade to the latest windows 10. I have a duplicate small screen. How do I get rid of it?

:)

 

Duplicate small screen

Hello i have a small duplicate screen in top left hand side of screen

 

Small Duplicate Screen at top left corner of monitor

Hi Henry,

It's possible that a third-party program caused the appearance of this small duplicate screen on your monitor. We'd like to learn more about your concern so that we could provide the proper resolution. We just have a few questions for you:

• Which build version of Windows 10 is on your computer? To check, click
  Start, type winver, and press Enter. For example, 14393.1066.
• Did you make any changes to your computer before this started happening?
• Did you get any specific error messages? If yes, please post them here.
  
• What troubleshooting steps have you done so far?

We'd like to see this small duplicate screen so that we could study it better. Please post a screenshot in your reply by following the steps

here.

As an initial recommendation, we suggest performing a
clean boot to find out if this behavior is caused by a third-party program. This will load Windows with minimal drivers and programs, preventing software conflicts from occurring. If the duplicate screen stops occurring in a clean boot environment, check
the section How to determine what is causing the problem by performing a clean boot for what to do next.

Note: To return your computer back to normal, check the section
How to reset the computer to start normally after clean boot troubleshooting.

We'll wait for your response and the result of the initial troubleshooting.

 

Duplicate small screen

Which device do you have, running which OS version ?