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Task Manager
Right-click the Taskbar and choose Task Manager to open it. Or alternatively, simply press Ctrl+Shift+Esc. Find Windows Explorer in the Process list, and click the Restart button at the bottom right corner.
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Command Prompt
If you are having trouble opening Task Manager, running the following two command lines in a Command Prompt would do the same.
taskkill /f /im explorer.exe
start explorer.exe
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You can save the two command lines in a batch file so you can easily run it by just double-clicking it.
PowerShell
This is going to be by far the easiest. Open a PowerShell console and run the following cmdlet and watch the Explorer process to be killed and restarted.
Stop-Process -ProcessName explorer
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