How to Repair MBR in Windows 11 in 2 Ways

Help, my PC won’t boot due to MBR error!

“My PC runs on Windows 11 and this morning, I found it wouldn’t boot and what appeared on the screen was ‘Error loading operating system’. I had heard about it and knew it was caused by corrupted MBR. However, I’m a novice in computing and have no idea how to repair MBR in Windows 11. Could anybody give me some advice?”

What is MBR?

MBR, short for Master Boot Record, is a special type of boot sector found at the beginning of your system partition. It holds info about the partitions of your hard drive and performs as a loader for the OS you are running on. MBR is created by the MBR generator the first time you install the OS on an MBR disk and it is the first 512 bytes of your hard disk.

What happens when MBR is corrupted?

Many things can cause corrupted MBR including improper unplugging, sudden power failure and virus infection. When MBR is corrupted, you can’t boot into your OS and also, error messages will keep prompting you. If you receive the following error messages while booting your PC, it means MBR is corrupted on Windows 11.

1. Error loading operating system

2. Operating System not found

3. Invalid partition table

4. No bootable medium found

5. Reboot and select proper boot device

2 Ways to repair MBR in Windows 11

If you come across any of the above error messages, don’t panic, because there’re still fixes to help you out. The first method is using Windows built-in tool Command Prompt while the second method is to resort to a powerful third-party disk manager.  

Method 1. Fix MBR via Command Prompt

When it comes to command line repair MBR windows 11, you can try the following 2 ways.

Way 1. Reboot the OS and once you see the Windows 11 logo, press and hold the power button to force the PC to shut down. Repeat the steps 2~4 times and you’ll see boot options.

Way 2. Boot our PC from Windows installation media, hit the option “Repair your computer” and then, “Troubleshoot”. Now, you Windows 11 boot options will appear.

In the window of “Advanced Options”, select “Command Prompt”. Then, input command lines “bootrec.exe” and hit “ENTER” to check all options available. There’re up to 4 parameters in total and they are /FixMbr, /FixBoot, /ScanOs, and /RebuildBcd. Each of them has its distinctive duty in solving Windows 11 boot errors.

Execute the order of “/FixMbr” on Windows 11 with Command prompt if you encounter these error messages “Operating System not found”, “Error loading operating system”, and “Missing operating system”, or “Invalid partition table”.

Method 2. Rebuild MBR with a third-party disk manager

Command Prompt is indeed a powerful and versatile tool to fix Windows boot errors. However, if you’re not a computing professional, you may find it’s suffering to drift among different command lines; or sometimes, you don’t have a Windows installation media. Thus, there’s another easier and more user-friendly tool – AOMEI Partition Assistant Standard – which helps rebuild Windows 11 MBR in only a few clicks. More than this feature, with it, you can also perform other disk management operations including formatting hard drive and checking partition.

Free download the most powerful disk management software utility to repair MBR in Windows 11 with ease!

Step 1. Install and launch AOMEI Partition Assistant Standard on a normal computer. On the interface, hit "Tools" in the top navigation bar and choose“Make Bootable Media” where the screenshot shows and follow the onscreen guide to create a Windows 11 bootable USB stick.

Step 2. Plug the USB into the problematic computer and enter the BIOS, change boot order, and boot computer from the USB drive.

Step 3. On the main interface of the software, click right click on the system disk that contains the broken MBR and select “Rebuild MBR”.

Step 4. In terms of your OS, select a type of MBR for Windows 11 in the popup window.

Step 5. After returning to the main interface, hit “Apply” on the upper left and then, “Proceed” to commit the MBR rebuilding process.

Notes:

1. “Rebuild MBR” can only fix issues like damaged MBR code. Other issues like unbootable OS caused by bootable file or system file missing can’t be dealt with by using this software

2. “Rebuild MBR” won’t cause any sort of data loss. However, improper conduct may make your PC unbootable. In this case, you’re suggested to learn more relevant computing knowledge and skills before performing MBR rebuild.

Conclusion

How to repair MBR in Windows 11 when your PC fails to boot due to MBR corruption? To help deal with it, this post recommended 2 powerful tools – Windows 11 built-in command prompt and third-party AOMEI Partition Assistant – to help you out. Since I seldom know any knowledge about computing, I prefer the second tool and indeed, I could use it without any obstacles. By the way, there’re many other features in this freeware including OS migration and partition splitting. If you want to try these features, you should upgrade to the Pro edition.