How to Quickly Fix Master Boot Record on Your Windows 10

By | January 14, 2022

The Master Boot Record (MBR) is a special type of boot sector found at the beginning of your system partition. The MBR tells the boot process what to follow, such as partition layout, size, file system, and so on. The MBR also traditionally contains a small piece of executable code that goes through the boot process to the proper operating system, landing you inside Windows.

MBR can’t go wrong. It can become corrupt, corrupt, or simply disappear, for a number of reasons. This makes the Windows 10 installation error prone. Fortunately, there are several ways to fix master boot records in Windows 10.

Causes of Startup Failure in Windows 10

How do you know when your MBR is failing? There is a very strong chance your system will fail to boot into Windows. Instead, you’ll be met with a screen with an error message stating “Operating system does not exist,” “MBR error,” “Error loading operating system,” “Invalid partition table,” or similar.

Master boot record corruption can occur for a number of reasons. Drive failure and damage is a very common cause. In recent years, certain ransomware variants have attacked master boot records to force victims to pay to secure their systems. Fortunately, this ransomware practice is rare, although many other examples of malware directly alter the MBR for maximum damage and irritation.

That said, there are several effective ways to repair Windows master boot records. If one fix doesn’t work for your system, try the next one.

Startup Repair via Windows Automatic Repair

When you first boot your Windows 10 system, it will detect that there is a problem and enter Automatic Repair mode. Your PC reading screen is not starting properly. From here, select Advanced options > Troubleshoot > Startup Repair.

The Windows 10 Startup Repair Tool is fully automatic. However, this took a long time to complete, but should fix your Windows 10 MBR issue.

Command Prompt via Windows Automatic Repair

If the Windows 10 Startup Repair process doesn’t fix your MBR issues, or you prefer a faster and more direct approach to repairing your system, you can use Command Prompt via Automatic Repair. When your system detects a problem and the Automatic Repair screen appears, select Advanced Options > Troubleshoot > Command Prompt.

You will use the bootrec.exe tool to repair the corrupted MBR. Bootrec has a set of commands designed to recover the boot process from problems and are already present on your Windows 10 system as part of the basic installation.

Type bootrec.exe /fixmbr and press Enter. Then type bootrec.exe /fixboot and press Enter. You will see Operation completed successfully under each command. If you don’t see the operation completion message and instead receive an error, enter bootrec.exe /rebuildbcd and press Enter. The “rebuildbcd” command tries to rebuild your system’s Boot Configuration Data (BCD).

This doesn’t always work the first time. In this case, Microsoft recommends exporting the BCD store (where your boot data is stored) and rebuilding completely from scratch. It sounds scary, but it only takes a short time.

Enter the following commands in order:

bcdedit / export c:bcdbackup
c:
boot cd
attrib bcd -s -h -r
ren c:bootbcd bcd.old
bootrec.exe / rebuildbcd

The export and rebuild process should completely fix your MBR issue.

Users who are still working with Windows 7 or earlier can also use the bootrec.exe /scanos command. This command scans for and repairs old BCD settings.

If You Can’t Access Command Prompt via Automatic Repair

Some users will find that Windows 10 Automatic Repair doesn’t show up when they want it. In this situation, you need to use your Windows installation media to boot into repair mode.

If you don’t have your Windows installation media, you need to find a working Windows system that you can use to create media.

However, there is one more solution you can try if you don’t have a Windows installation drive or disc. You can trick your system into thinking there was a boot failure by turning it on, then shutting it down again when the Windows logo appears.

After you repeat this process three times in a row, Automatic Repair will trigger. Please note that this will not work for everyone, depending on your system status.

Fix MBR Problems in Windows Using GParted Live

GParted Live is a bootable Linux distribution with a focus on partition management. However, it also allows you to work on your Windows partition outside of the operating system, which means you can try to repair and restore your MBR issues. To complete this part of the tutorial, you will need a working alternative system.
Download GParted Live

First, you have to download GParted Live. There are two versions. If you have a 32-bit system, choose the i686.iso version. This version works on both 32 and 64-bit systems, though with some limitations. If you have a 64-bit system (and you are sure it is a 64-bit system!) Download the amd64.iso version.

Write GParted Live to Bootable Media

Next, you need to write the disk image to a bootable media type. I’m using an 8GB USB flash drive, but a smaller drive will work, as well as a suitable disk. You should also download UNetbootin. Open UNetbootin. Select Diskimage at the bottom of the panel, then hit the three-dot icon to browse to the GParted Live ISO.

Thanks For Visit

Select ISO and press Open. Then select the USB flash drive you want to write GParted Live to as well and hit OK. Once done, remove the bootable media and shut down your system.

Boot Into GParted Live

Insert the bootable GParted Live media into the system with the corrupt MBR. Power on the system, pressing the boot process hotkey for your system to open the boot device selection menu (for example, F11 on my PC and laptop). You should look at GParted Live media as a potential bootable source. Select it and let the media load. You have to make some small choices, such as language and operational mode.

Using GParted Live and TestDisk to Repair MBR

Once the Live GParted environment is loaded, open a Terminal window, type sudo fdisk -l and press Enter. This command will list all the drives and partitions currently available on your system. Now, open a new Terminal window, type testdisk, then select No Log.

Next, it will ask what disk you want to repair. Select your drive, then Continue.

Now, select the partition table type. In this case, select the Intel / PC partition, and press Enter.

Select Analysis, then Quick Search.

TestDisk will scan your drive for existing and previously deleted partitions. The scanning process may take a few minutes, depending on the size of the drive. Finally, it will identify your primary system partition. It looks a little confusing, but you want GParted Live to list all your system partitions.

We look for the partition with “*” – this is your primary Bootable partition and is where the corrupt MBR is hiding. If the scan doesn’t show all your partitions, select Deep Search. Next, GParted will give you a short list of information in case of errors.

If all your partitions show up with the correct flags (like bootable, extended, logical) then (and only then!) write them to the partition table. If the flag is not correct, toggle it by using the arrow keys. For example, in the following screenshot, the first image shows a drive with a duplicate second partition ([Partisi 2]). Scrolling through a partition and pressing P shows the files found on that partition.


The first duplicate partition is corrupted, as evidenced by Cannot open filesystem. The system message seems corrupted.


The second duplicate partition contains a list of file folders and is therefore the correct partition.

The flag for the first duplicate partition is then set to D for Delete, while the second duplicate partition is set to L for Logical, returning the partition and its data to the drive.

When you return to the TestDisk menu, select MBR Code to write the standard MBR to your disk, and confirm.

You have done. You can close the Terminal window, exit GParted Live, and shut down your system. Remove the GParted Live bootable media, and reboot your system.

Fix MBR Problems in Windows Using Boot Repair Disk

Boot Repair Disk is another very useful Linux distribution that you can use to fix Windows 10 MBR problems. In fact, the Boot Repair Disk includes a copy of GParted, just in case. However, it simplifies the MBR restoration process into a single program with an easy-to-change box.

First, download the 64-bit or 32-bit version of the Boot Repair Disk, depending on your system. Like the GParted Live image, the 32-bit version only works with 32-bit systems, while the 64-bit version works with both.

Write Boot Repair Disk to Bootable Media

Next, you need to write the disk image to a bootable media type. I’m using an 8GB USB flash drive, but a smaller drive will work, as well as a suitable disk. You should also download UNetbootin.

Open UNetbootin. Select Diskimage at the bottom of the panel, then hit the three-dot icon to browse to the Boot Repair Disk ISO.

Select ISO and press Open. Then select the USB flash drive that you want to write the Boot Repair Disk to as well and hit OK. Once done, remove the bootable media and shut down your system.

Boot To Boot Repair Disc

Insert your Boot Repair Disk media into the system with the corrupted MBR. Power on the system, pressing the boot process hotkey for your system to open the boot device selection menu (for example, F11 on my PC and laptop). You should see a flash drive or Boot Repair Disk disk as a bootable source. Select it and let the media load.

Using a Boot Repair Disc to Repair the MBR

Once the Boot Repair Disk environment is loaded (Boot Repair Disk uses the lightweight Lubuntu environment), select LXTerminal from the taskbar. Type fdisk -l and hit Enter to list your current drives and partitions.

Next, select the B logo in the bottom right (where the Windows Start menu lives), and head to System Tools > Boot Repair. The program will scan your system, then you can select an Automatic repair session or view Advanced Options. First, try the Automatic repair option. Automatic repair fixes most boot problems right away.


If that doesn’t work, go to Advanced options and head to the MBR options tab. Cross reference with the list of drives and partitions in the previously created LXTerminal session, locate your Windows boot partition. Boot Repair Disk doesn’t mark it a little more clearly than the basic Live GParted command! Once you are sure, hit Apply, then restart your system.


Fix MBR Issues Using EaseUS Partition Master

This final fix requires you to remove the physical drive from the system in question. After you wipe the drive, you can connect it to another system and use EaseUS Partition Master to repair the MBR.


Download and install EaseUS Partition Master, then connect the drive. Select an external drive. (It will have an MBR label.) Right-click the drive label and select Rebuild MBR. Head to the top right corner and hit Apply, then let the process finish. Erase the drive, then reinstall it on the original system, and reboot.

Thanks For Visit

Category: