Press Ctrl + Shift + Esc to open Task Manager
Select the unresponsive app
Click End task
Press Alt + F4 to close the active window
If the app is frozen, press Ctrl + Alt + Delete
Open Task Manager from the menu
Select the app and click End task
Right-click the taskbar and choose Task Manager
Use the Processes tab to find the app
Select it and click End task
If needed, restart the PC