How do I close an app that is frozen and will not close?

You'll be able to: Force close a frozen or unresponsive application

The steps

1
Press CtrlShiftEsc together on your keyboard. A window titled Task Manager opens immediately on top of your screen.
What does Task Manager do?
Task Manager is Windows' master control room. It shows every app currently running and has the authority to immediately shut down any app that has stopped responding.
2
Look for the frozen program in the list under Apps (it may say Not responding next to its name). The frozen program appears in the list.
3
Click the frozen app to select it, then click the End task button in the top bar or bottom-right corner. The frozen application instantly disappears from your screen and ceases running.
Tip
Once the frozen app is gone, you can close Task Manager and reopen the app normally.

It looks different on my screen

If Task Manager opens as a tiny minimalist window with no buttons, click More details at the bottom to expand the full list of running programs.

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