Deleting Extra Explorer.exe Keys
1. Open the Task Manager by pressing 'Ctrl,' 'Alt' and 'Delete' keys simultaneously. Click on 'File' and select 'New Task (Run)' from the menu. Type 'regedit.exe' into the dialog box. Press 'Enter.'
2. Click on 'Edit' and click on 'Find.' Type 'explorer.exe' into the search box. Press 'Enter.'

3. Delete any appearance of 'explorer.exe' other than in 'HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\WinLogon\Shell.' Save the changes and restart the computer.
Repairing Explorer.exe
4. Click on the 'Start' menu. Type 'cmd' in the search box. Right-click on the icon at the top of the window and choose 'Run as Administrator.'
5. Type 'sfc /scannow.' in the command prompt window, which initializes a system file checker that scans immediately for issues with Windows critical system files, . according to Microsoft. If explorer.exe is corrupt, the scan will repair it.
6. Restart your computer.