Fix: Unmountable Boot Volume On Windows 10 & 11

Recently came across the "Unmountable Boot Volume" error on Windows? We'll break down each tried-and-tested way to fix this blue screen error.

Errors in the “blue screen of death” category are the most worrying and challenging to encounter. Regrettably, they frequently catch us off guard and render our computers inoperable.

One of the more popular blue screen errors is the “Unmountable Boot Volume” error, appearing on both Windows 10 and 11.

This guide covers the problem in detail and provides multiple methods to help you fix it.

If you’ve recently encountered this error, keep reading to learn more.

Let’s get into it.

Table of ContentsShow

The Problem Explained

As many users stated across various forums and PC-support websites, the “unmountable boot volume” Windows error occurred without previous warnings causing their PC to be unusable until fixing the problem.

However, many users couldn’t fix the problem without taking more “drastic” measures, such as reinstalling their operating system from scratch.

But let’s take a step back and see what causes the problem.

As stated in the error message, the “unmountable boot volume” code signals an issue with the drive containing your operating system, so-called the “boot drive.”

Windows unmountable boot volume error

That could happen for numerous reasons, such as system files becoming corrupt, accidentally deleting a system file, BIOS misconfiguration, or hardware misconfiguration or failure.

Depending on the reason, there are various approaches to resolving this problem. You can find all relevant methods in the following sections below.

Fix 1: Restart Your PC

Restart PC

After a blue screen of death error occurs, the PC crashes and automatically attempts a reboot. In some cases, such as when the boot drive or system files are permanently damaged, the reboot will result in the same error.

However, in other situations, the reboot may be successful, and you can use that to try some of the different methods that can help you fix the problem permanently.

We recommend not instantly shutting down your PC out of fear after the blue screen crash but instead letting it attempt at least one reboot to see if it goes through successfully.

Later on, for further troubleshooting purposes (if a simple restart doesn’t fix anything), you’ll have to allow your PC to crash multiple times so that you can access the automatic repair screen whatsoever.

Fix 2: Check The Boot Settings In Your BIOS

Settings

The BIOS is responsible for many functions and controls your computer’s behavior to a large extent. Your computer’s BIOS is also where you tell your computer which disk to “recognize” as the primary boot drive.

After your PC crashes, during the reboot process, there are shortcuts available (different for each motherboard mode, so you’ll have to look it up for your specific case) that allow you to access the BIOS. Within the BIOS, you’ll find a dedicated “BOOT” section where you can set a drive as the primary boot volume.

If you have an incorrect drive set as the boot volume, other than the one where Windows is on your PC, you may see a similar error or the same one. Make sure the accurate drive is selected.

Fix 3: Re-Plug Your HDD Or SSD And Test On Other Device

SSD

Your PC may be unable to boot for a few reasons, one of that may be a failing hard drive or SSD.

To rule out a hardware problem, we recommend unplugging and plugging the drive (your main drive on which the operating system is) back into the PC and attempting a boot. If the boot fails, the next step is to unplug the drive and test it as a regular drive on a different computer.

If the drive doesn’t work on a different PC and shows signs of malfunction, it’s likely a hardware failure, in which case there aren’t many options besides acquiring a new one and installing Windows on it, then set that one as your default boot drive.

Fix 4: Use The Automatic Repair Feature

Fix or Troubleshoot

When Windows errors become serious, we rely on the Automatic Repair feature to fix them. However, this is tricky as it requires users to have a DVD or a USB drive with a legitimate, working Windows 10 installation setup.

If you’ve experienced this error unexpectedly and don’t have a drive with the Windows installation files, you’ll have to acquire one before proceeding. You can use a laptop or a different PC for this task if your computer is momentarily unusable due to the error.

We have a detailed guide covering how to create a bootable Windows USB that you’ll need for this method.

Once your drive with Windows installation files is ready, follow the steps below to try and fix the “Unmountable Boot Volume” Windows error using the Automatic Repair Feature.

  1. Plug the USB (or insert the DVD) into your PC and power it up.
  2. Choose Repair Your Computer from the list of options. Sometimes this may not show up immediately, and you’ll have to “allow” your PC to crash once to get this option.
  3. Click Troubleshoot.
  4. You’ll see a list of options on which you need to find Startup Repair and click it.
  5. Follow the setup and on-screen instructions to complete the process.

When done, reboot your PC and see if the troubleshooting process was successful. In some cases, this will automatically fix the problem.

Here’s a helpful video showing the process from beginning to end if you need a visual representation of the steps:

If it doesn’t, move on to the other fixes below.   

Fix 5: Fix The Main (Master) Boot Record

Fix

For this fix, you need to have the USB or DVD plugged into your PC like during the previous method.

With the install media in your PC, follow the steps below:

  1. Power up your PC and choose Repair Your Computer. Then, click Troubleshoot.
  2. In the list of advanced options, click on Command Prompt.
  3. Once the panel loads, type in bootrec /fixmbr and press Enter to initiate the command. 
  4. Wait for the process to complete, then type in bootrec /fixboot and press Enter.
  5. Once that process is complete, type in the third and final command, bootrec /rebuildbcd, and press Enter on your keyboard.
  6. Type exit and press Enter to exit the Command Prompt, then restart your PC.

Hopefully, this will fix the problem, as the method was proven helpful in many cases.

Fix 6: Run The Disk Check Command

Command

This fix is another Command Prompt method that can help you resolve the “Unmountable Boot Volume” Windows error, similar to the previous one.

This is what you should do:

  1. Boot your PC from the bootable USB or Recovery DVD as you did during the previous two methods.
  2. Once your PC boots, you’ll see the Repair Your Computer option. Click it, and then click Troubleshoot.
  3. Open the Command Prompt.
  4. Now, type in chkdsk /r c: and press Enter on your keyboard. If you have Windows installed on a different drive, change the “c” letter with the letter of the drive assigned as the primary boot volume.
  5. Now, allow the process to scan for any drive errors. Depending on your computer’s performance, this process could take a while, sometimes more than thirty minutes.
  6. If there are any issues, the setup will allow you to resolve them.

When done, reboot your PC and check if the problem persists. Hopefully, your PC will now boot without the BSOD crash.  

Fix 7: Reinstall Windows – Format The PC

Installation

Last but not least, if you cannot solve the problem in any way, we recommend formatting your PC. You can do this using the repair DVD or bootable USB you created for some of the previous methods listed in this guide.

Sometimes you can “get away” only by resetting Windows without losing your files. However, in some cases, you’ll have to perform a clean reinstall.

Conclusion

That concludes everything you should know about the concerning “unmountable boot volume” error on Windows. Though it’s a relatively frequent error, it’s still difficult to deal with, and it sometimes results in the user having to reset their PC and lose their files.

Hopefully, you’ll fix it using some of the methods listed in this guide, as they helped other users and should help you too.

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Bojan Veselinovikj
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Bojan is a video-game developer and a tech enthusiast. Combining these two passions allow him to keep you informed on everything that's new in this fast-paced digital world.