Power on and off your computer three times
On the third time, your computer will boot into the Advanced Recovery environment
Click Advanced Options
Click Troubleshoot
Click Advanced Options
Fix 1 - Run Automatic Repair
- In the menu, choose Troubleshoot > Advanced Options > Startup Repair.
- Next, select the target operating system to fix. Windows will initiate the repair and then restart.
Fix 2 - Use SFC /SCANNOW to Repair System Files
- In the menu, click Troubleshoot > Advanced Options > Command Prompt.
- In the command line, type sfc /scannow and press Enter button.
- Restart your computer when the process is finished.
Fix 3 - Run CHKDSK to Repair Boot Drive
- Open Command Prompt using the steps in fix 2, type chkdsk /r c: and press Enter.
- Type Y and hit Enter when you are prompted to schedule the check after a reboot.
- Reboot and let the check proceed. It might take a while.
Fix 4 - Fix MBR
Open Command Prompt, type the following commands and press Enter after each move.
bootrec /rebuildbcd
bootrec /fixmbr
bootrec /fixboot
exit
If that does not work.
Go to a working computer, download, create a bootable copy, then perform a clean install.
Step 1: How to download official Windows 10 ISO files
[http://answers.microsoft.com/en-us/windows/wiki...](http://answers.microsoft.com/en-us/windows/wiki/windows_10-windows_install/how-to-download-official-windows-10-iso-files/35cde7ec-5b6f-481c-a02d-dadf465df326)
Step 2: How to: Perform a clean install of Windows 10
[http://answers.microsoft.com/en-us/insider/wiki...](http://answers.microsoft.com/en-us/insider/wiki/insider_wintp-insider_install/how-to-do-a-clean-install-of-windows-10/aef0ae63-2117-41ee-a8ea-4a3181625b08)
If there are files on the drive you want to recover, see - How to: Perform a Custom install of Windows 10
[http://answers.microsoft.com/en-us/insider/wiki...](http://answers.microsoft.com/en-us/insider/wiki/insider_wintp-insider_install/how-to-do-a-custom-installation-of-windows/38adfa8c-32f8-4354-8c53-13b5f2cf7e44)