Mbr Repair Software — Hard Drive

: Select Repair your computer > Troubleshoot > Advanced options > Command Prompt .

This is the most direct method and doesn't require downloading extra software if you have a Windows installation or recovery USB. Hard Drive Mbr Repair Software

bootrec /rebuildbcd — Scans for installations and rebuilds the Boot Configuration Data. How Do I Fix the Master Boot Record (MBR)? : Select Repair your computer > Troubleshoot >

bootrec /fixmbr — Writes a new Windows-compatible MBR to the system partition. Hard Drive Mbr Repair Software

: Insert your Windows installation USB/DVD and boot from it.