The MBR or the Master Boot Record is a special kind of sector that can be found at the start of the system partition of your computer. The MBR manages the boot process and helps your computer understand how everything, such as partition layout and the file system, will be handled after the boot process is complete. In simple terms, it helps your computer boot and the Windows 10 OS (operating system) work afterward. Still, even the Windows MBR can get damaged or corrupted for various reasons. Luckily, there are multiple ways to recover MBR for Windows 10.
In this article, we will discuss why Windows MBR fails and how to restore it to working order using simple and relatively quick methods. Let’s dive in.
Why Does Windows 10 MBR Fail?
If you’re using your device for a long time, there is always a chance for the Windows 10 MBR to fail. When this happens, instead of booting directly to your sign-in screen, your computer will one of the following messages:
- Missing Operating System
- Error loading operating system
- MBR Error
- Invalid partition table
If you see one of these messages or any other similar message, it would mean that your Windows MBR has suffered a severe case of corruption. This problem can happen for multiple reasons.
One of the most common reasons for a corrupted Windows MBR is hard disk drive (or solid-state drive) failure. On the other hand, it can also occur because of a vicious ransomware infection, which attacks the master boot record (MBR) and encrypts it. Consequently, the cybercriminals behind the attack would force their victims to pay to recover their system. Fortunately, the ransomware attacks that directly target the Windows MBR are quite rare. However, other malicious software or viruses can still attack the master boot system and lead it to its corruption.
As you can see, the Windows MBR can fail for several reasons, even without a warning. Thankfully, there are a handful of key strategies to restore the master boot record. In this section, we will show you three methods to easily repair MBR.
1. Recover Windows 10 MBR Using Startup Repair
If your Windows 10 MBR is corrupted, the system should notice it when you boot into your computer. Now:
- The Windows 10 operating system should automatically enter into the “Automatic Repair” mode. Once it does, you should see a prompt for “Automatic Repair” mode with this message: Your PC did not start correctly.
- Now, navigate to Advanced options → Troubleshoot → Startup Repair.
- Next, the Windows 10 “Startup repair” tool will automatically check the system, and it should fix the issues related to the master boot record.
2. Use Command Prompt After Going through Automatic Repair
If the “Startup repair” tool fails to fix the issue or you want to fix the MBR using a more direct approach, you can always use the “Command Prompt” through the “Automatic Repair” option. Here’s how you can do it:
- First, once the “Automatic Repair” prompt appears, navigate to Advanced Options → Troubleshoot → Command Prompt. Now, you will be using the “bootrec.exe” tool via the Command Prompt to fix the MBR failure.
- Now, type the “bootrec.exe /fixmbr” command and press the “Enter” key to execute it.
- Next, type “bootrec.exe /fixboot” and press the “Enter” key again.
Please note that you should see this message under each of the previous two command lines: The operation completed successfully. If you don’t see that success message and see an error message instead, type the “bootrec.exe /rebuildbcd” command and press the “Enter” key. This command will try to rebuild the computer’s Boot Configuration Data (BCD).
However, this command doesn’t always work when you use it for the first time. In this case, you need to export the BCD store and rebuild the BCD from scratch. But don’t worry. It may sound like a lot of work, but it will only take you a minute or two. All you need to do is enter the following command lines in the given order:
- bcdedit /export c:\bcdbackup
- cd boot
- attrib bcd -s -h -r
- ren c:\boot\bcd bcd.old
- bootrec.exe /rebuild
Once you complete typing and executing these commands, you should be able to recover the Windows 10 MBR without an issue.
What if You Can’t Access the Command Prompt via Automatic Repair
Sometimes, the Automatic Repair option might not appear even after you boot your computer. Without it, you can’t access Command Prompt. In this case, you would need a bootable Windows installation media, go to the Repair Mode, and access it from there. However, if you don’t have a bootable Windows installation media, you have to find a working computer with Windows 10 OS to create one.
You can also power on your computer and power it off just when the Windows logo appears to make your computer think of it as a boot failure. If you do this three times quickly, it will trigger the Automatic Repair option. Unfortunately, even though this has a high chance of success, it might not work for everyone. Thus, if the “Automatic Repair” option doesn’t appear, and you also don’t have a bootable Windows media drive or CD, you can always use the method we are about to share.
3. Recover Windows 10 MBR Using GParted Live
GParted Live is a bootable version of Linux distributions that works on partition management. But this Linux distribution also allows you to work on the Windows partitions without altering the operating system. In other words, any Windows 10 user can employ it to solve their MBR problems. Thus, as long as you have another functioning device, you can download GParted Live, make a bootable media out of it, and use it to fix your MBR troubles. In this section, we will show you exactly how to do it. Let us start by downloading the GParted Live.
1. Download GParted Live to Your Computer
To continue using this method, you need to download the GParted Live Linux distribution first. GParted Live has two different versions. These two versions are i686.iso and amd64.iso. If you’re not sure whether your device has a 32-bit or a 64-bit system, you should download the i686.iso version. This version works best on the 32-bit systems. But it also works on the 64-bit systems with a few limitations. If you’re sure that your device has a 64-bit system (we mean it—only if you’re convinced), you should download the amd64.iso version of the GParted Live Linux distribution.
2. Using GParted Live to Make a Bootable Media
Now, you need a flash drive, CD, or any other storage media and write the GParted Live in it to make a bootable media. If you’re using a flash drive, a 4 GB one will be enough. You need to download and install the “UNetbootin” application on your other working computer. We will use this application to make a bootable media using the GParted Live Linux distribution.
Here’s how you can do it:
- Open the UNetbootin application on your computer and click on the “Diskimage” option at the bottom left side of the window.
- Next, open the “three-dot icon” to open a browsing prompt and select the “GParted Live.iso” option.
- After that, click on the drop-down menu and select the “ISO” option beside the “three-dot icon.”
- Now, click on the drop-down menu beside the “Type:” text and select the storage media type you will be using to create a bootable media.
- Next, select the drive and click on the “OK” button.
Once you’re done, remove the newly created bootable media from the computer.
3. How to Boot Using GParted Live
Once you get the bootable media using the previous steps, connect the bootable media with your computer with corrupted Windows 10 MBR. Once you’re done, follow the steps below to boot into your computer using the bootable media:
- Power on your computer and keep pressing the boot process shortcut key to enter into the boot selection menu on your computer. The shortcut key may vary depending on the manufacturer of the computer. But usually, the shortcut keys are one of these: Esc, F2, F9, F10, F11, or F12. You can check the information on your computer manufacturer’s official website.
- Find the GParted Live media you have created in the list of bootable options and select it.
- Let the computer boot using the GParted Live media. You might need to make some minor edits before the boot, such as setting the date, time, and language. But once you finish, you should boot right away.
4. Recover the MBR for Your Windows 10 PC
Once the GParted Live Linux distribution loads into your computer, open Terminal and follow these instructions:
- Type the “sudo fdisk -I” command and press the “Enter” key. This command will check all the drives and partitions available on your computer and make a list of them.
- After that, open a separate Terminal and execute this command: testdisk
- Now, select “No Log” from the available options.
- The “TestDisk” will ask which disk you would like to repair. In this case, select your computer’s hard disk drive and then select the “Proceed” option.
- Now, from the partition table type, select the “Intel/PC partition” option and press the “Enter” key.
- After that, choose the “Analyze” option and then the “Quick Search” option.
Now, wait for the TestDisk utility to look for any previously deleted partitions from your computer. It will take a while, and after that, locate the primary partition. Sure, it will take a few minutes, and it might even be a little confusing. But be patient because it would be best for GParted Live to identify all the system partitions on your Windows 10 device.
5. Selecting the Corrupted Windows 10 Partition
Next, we will search for the partition with an “*” icon. This is your system’s primary bootable partition, and it’s also the place where the corrupted Windows 10 MBR is. If the “Quick Search” doesn’t give you any partition with an “*” icon, you should opt for the “Deep Search” option. Once all your partitions show up with the correct flags (for example, bootable, logical, or extended), it’s time to write the MBR code to the partition table. If the partitions are not correctly flagged and have duplicate partitions in the list, you can fix them by editing them using the directions shown in the TestDisk utility.
After you’re done fixing, choose the “MBR Code” option to write a standard version of Windows MBR in your primary drive, and then confirm it. You’re done! Now, close Terminal, sign out of GParted Live, shut your computer down, and take the bootable media out. You can now reboot into your Windows 10 computer since you’ve successfully recovered MBR.