How to Fix Bootrec Issues and Rebuild the Boot Configuration Data (BCD) in Windows

If you’re experiencing boot issues with your Windows computer, the bootrec utility can be a powerful tool to help resolve problems with the Master Boot Record (MBR), boot sector, and Boot Configuration Data (BCD). This guide will walk you through the steps to fix bootrec issues and rebuild the BCD in Windows Vista, 7, 8, 8.1, and 10.

Accessing bootrec.exe in Windows Recovery Environment

To access the bootrec.exe utility, you’ll need to boot into the Windows Recovery Environment (WinRE). You can do this by:

Booting from the original Windows installation media (DVD or USB drive)
Using a recovery drive or USB drive created with the Windows 10 Media Creation Tool
Tapping the F8 key rapidly during startup to access the Advanced Boot Options menu (this method may require several attempts)

Once you’ve booted into WinRE, follow these steps:

Select “Repair your computer” or “Troubleshoot” from the options presented
Choose “Command Prompt” from the list of recovery tools
Type the desired bootrec commands at the prompt

bootrec Commands and Parameters

The bootrec utility offers several commands to help fix boot issues:

bootrec /FixMbr: Writes a Windows Vista/7/8/10-compatible Master Boot Record to the system partition
bootrec /FixBoot: Writes a new, Windows-compatible boot sector to the system partition
bootrec /ScanOs: Scans hard drives for installed Windows versions and lists them in the BCD
bootrec /RebuildBcd: Scans for installed Windows versions and allows you to select which to add to the BCD

To use these commands, simply type them at the command prompt and press Enter. If the operation is successful, you should see a message indicating that it completed successfully.

Repairing the EFI Bootloader on GPT Drives

If your computer uses a GPT hard drive and UEFI firmware, you may need to take additional steps to repair the EFI bootloader:

Use the diskpart utility to assign a drive letter to the EFI system partition (ESP)
Navigate to the \EFI\Microsoft\Boot\ directory on the ESP
Run bootrec /FixBoot to write a new boot sector

If you’re unable to boot into WinRE, you can also try using a Windows 10 installation or recovery drive to access the command prompt and run these commands.

Keep in mind that while bootrec can be a powerful tool for fixing boot issues, it’s always a good idea to have a recent backup of your important data before attempting any repairs. If you’re unsure about the process or encounter any issues, it’s best to seek assistance from a qualified technician.