Repair or rebuild Master Boot Record (MBR) on windows 10

Getting different Startup error messages like “Operating System not found”, “Bootmgr is missing“, “bootrec element not found”, “Error loading operating system”, “Missing operating system” or “Invalid partition table”. All these error codes are symptoms of  Master Boot Record Error. Maybe MBR (Master Boot Record) is missing or Corrupted on your Windows 11 or windows 10 computer. Here in this post, we discuss What is MBR?, And How to repair or rebuild Master Boot Record (MBR) on Windows 11 To fix windows Startup problems.

What is MBR (Master Boot Record)?

The Master Boot Record (MBR) holds information about the partitions of your hard drive. That enables your PC to find and identify the location of the operating system to allow Windows 11 or windows 10 to boot properly. If Due to any reason such as Virus/ malware infections, Improper shutdowns, data corruption as well Other reasons Master Boot Record (MBR) get corrupted or missing from your computer you can’t get past the BIOS loading screen and you’ll get an error message that the boot information is not found, Operating System not found”, “Bootmgr is missing”, “bootrec element not found etc.

Repair Master Boot Record

If the MBR is damaged, you won’t be able to boot into Windows. Most people think to re-install the OS to fix this type of issue. But it’s not required Here is how to fix MBR and Repair/rebuild Master Boot Record (MBR) on Windows 10.

If due to Missing MBR we are unable to boot windows normally, That cause we need to access Advanced options where we can access the Advanced command prompt to Repair/rebuild Master Boot Record (MBR).

  • To do this first insert your bootable windows media to your problematic PC.
  • If you don’t have any then Download the latest Windows 10 ISO and Create a Bootable USB/DVD drive following the steps here.)
  • Restart your PC and Press ESC or Delete key (Some PC support F12, F2) To Access BIOS setup.
  • Then Change the boot order To Boot your computer with the bootable media to start the Windows 10 Setup.
  • Press Any Key to boot from installation media, and skip the first screen.
  • And on the next screen click on  Repair your computer on the lower-left corner.

Repair your computer

  • Next, Click Troubleshoot followed by Advanced options then Command Prompt To Access Advanced command prompt to fix MBR.

Advanced options Windows 10

Now perform the command below to fix MBR and make your PC boot again normally.

When you are on advanced command prompt this will allow you to launch the  Bootrec.exe tool to repair the Master Boot Record on your Windows 10 PC. Bootrec.exe  supports a number of options depending on your situation. So First use the fixmbr command with bootrec tool to repair the corrupted or damaged MBR.

  • bootrec /fixmbr

Once you execute the command, you will receive a confirmation message operation is completed successfully.

If you think your boot sector has been either damaged or replaced by the other bootloaders, then use the below command to erase the existing one and create a new boot sector.

  • bootrec /fixboot

Besides corrupted boot records, boot record errors may also occur when the “Boot Configuration Data” has been damaged or corrupted. In those cases, you need to use the following command to rebuild the Boot Configuration Data. If the BCD is actually corrupted or damaged, Windows will display the identified Windows installations to rebuild the entire BCD.

  • bootrec /rebuildbcd

If you have installed multiple operating systems on your Windows machine, then you might want to use the “ScanOS” argument. This parameter commands Windows to scan and add all the missing operating systems to the Boot Configuration Data. This enables the user to choose an operating system while booting.

  • bootrec /scanos

Fix MBR and Rebuild BCD

After that Type exit to close the command prompt and reboot windows. You should now able to boot your Windows PC again without any problem.

Fix Bootmgr Is Missing

If you are trying to troubleshoot a “Bootmgr Is Missing” error and rebuilding the BCD store doesn’t fix the problem, you can use the following commands to export and erase the BCD store and use the RebuildBcd command again to try getting Windows 10 to boot.

To do this again open the command prompt from Advanced options, And perform the following commands, press Enter on each line:

  • BCDedit /export C:\BCD_Backup
  • C:
  • CD boot
  • Attrib BCD -s -h -r
  • Ren C:\boot\bcd bcd.old
  • Bootrec /RebuildBcd

Press Y to confirm adding Windows 10 to the list of the bootable operating system on your computer

Fix Bootmgr Is Missing

After performing These commands Reboot the windows and check There is no more startup repair. And your system able to load Windows 10 without any startup errors.

Yes, it’s that simple to fix the MBR in Windows 10. Comment below if you face any problems while performing the above commands to fix the boot record errors. Also, Read

Steve Ballmer
With over 7 years of experience in the IT industry, I have experience in IT support, helpdesk, sysadmin, network admin, and cloud computing. Certified in Microsoft Technologies (MCTS and MCSA) and also Cisco Certified Professional in Routing and Switching.