In Windows 8.1 the Task Manager no longer lists Explorer.exe, but there is a way to restart Explorer.exe in Windows 8.1. Here’s how to restart Explorer.exe windows 8.1:
Open the Task Manager (Ctrl+Shift+Esc)
On the Processes tab, right click Windows Explorer (Yup, that’s the new name for Explorer.exe!)
If your Windows Explorer process isn’t in the list, Explorer.exe has probably crashed and died, or you’ve stopped the Windows Explorer process. Frustratingly, you’ll notice that the button to start a process is no longer available in Windows 8.1. To fix this and start Explorer.exe, in the Task Manager, click File -> Run new task.
If all else fails, you can always restart Windows to restart the Explorer.exe process.