Encountering the unmountable boot volume error can be quite frustrating, often stemming from issues like corrupted system files, hardware glitches, or misconfigured BIOS settings.
The unmountable boot volume is a common issue faced by Windows users, causing their system to become unbootable.
We’ll show you how to fix this error and get back into your PC. While these steps are aimed at Windows 10, they’re adaptable for Windows 11 too.
Table of Contents
What is the Unmountable Boot Volume Error?
The “boot volume” is the partition of your storage drive (an SSD or hard drive) that holds Windows. This error occurs when your computer can’t load Windows properly, resulting in a blue screen of death you’ll need to troubleshoot.
A “stop code” is the specific error message that identifies the problem Windows ran into when you see a blue screen—in this case, it’s the unmountable boot volume stop code.
Thankfully, this error doesn’t always mean that your storage drive is dying. Though that may be the case, we’ll walk through other troubleshooting steps for an unmount boot volume first.
What Causes Unmountable Boot Volume Error
Unmountable Boot Volume Windows is a critical error that can occur due to various underlying issues. Here are the most common causes:
- System file corruption: Corrupted system files can prevent the disk from being mounted and interfere with the boot process.
- Hard disk drive corruption: Physical damage to the hard drive or data corruption makes it difficult for the OS to load correctly.
- Boot volume corruption: Corruption of the boot volume’s file prevents the system from mounting the boot volume during startup.
- Damaged RAM: Data corruption caused by faulty RAM modules has the potential to slow down the boot process.
- Improper BIOS configuration: Incorrect settings in the BIOS could hinder the boot process and result in errors.
- Windows update error: System files might be disrupted by a faulty or incomplete Windows update, making the boot drive unmountable.
How to fix the Unmountable Boot Volume Error
Follow these steps to get your PC running again.
Step 1: Reboot and Check for the Error Again
Like most blue screen messages, the unmountable boot volume error isn’t always something to worry about if you only see it once. Sometimes Windows runs into a temporary hiccup that you never have an issue with again.
If you see the unmountable boot volume error blue screen while working, restart your PC and try to boot Windows up again. You should be clear if the error doesn’t return for some time.
Usually, though, you’ll see the unmountable boot volume error each time you try to boot into your PC, and it won’t let you load Windows at all. In that case, proceed with more in-depth troubleshooting.
Step 2: Create a Windows Install Disk
Since you can’t boot Windows normally to solve this issue, you’ll need to create a Windows installer on a USB drive or DVD using another machine. This will let you access the troubleshooting tools Windows offers by booting from a different device.
Thankfully, the Windows 10 Media Creation Tool makes it easy to create Windows 10 installation media. If you’re on Windows 11, use the Windows 11 download page for the same purpose.
Once you’ve created your installable disk, plug it into your PC and boot from the USB or DVD. You’ll probably need to change the boot order on your PC to do this. The exact method to do so depends on your computer.
Step 3: Use Windows’ Automatic Repair
Let Windows start from your USB drive until it loads up, then click the Next button. You’ll see the Install Now screen. But you don’t want to reinstall Windows; instead, click Repair your computer in the bottom-left.
On the following screen, select Troubleshoot and you’ll open a page of Advanced Options. Choose Startup Repair and choose the target OS: Windows 10 (or your current version).
From here, Windows will run an automatic repair that will hopefully take care of your issue. Once it’s done, exit the installer and try to boot your computer normally. If Windows still shows an unmountable boot volume error after this, continue to the next step.
Step 4: Repair the MBR or GPT
The Master Boot Record (MBR) or GUID Partition Table (GPT) contains information about where Windows is located on your hard drive and helps the OS load properly when you turn your computer on. If this becomes corrupted, it can lead to an unmountable boot volume message.
To repair the MBR or GPT, boot again from your Windows 10 or Windows 11 install media and select Repair your computer > Troubleshoot. This time, on the Advanced Options screen, choose Command Prompt.
At the Command Prompt, type the following command to run an MBR repair:
bootrec /fixmbr
Wait until it completes, then run the following commands one at a time to attempt additional repairs. If your disk uses GPT, these are the primary commands to attempt a fix:
bootrec /fixboot
bootrec /rebuildbcd
Type exit to leave the Command Prompt once these finish running. Then reboot again and see if the boot volume error continues to pop up. If it does, you might want to run advanced MBR troubleshooting.
Step 5: Run the Chkdsk Command
If the automatic repair and MBR/GPT repair don’t solve your problem, you should next try Chkdsk. This important Command Prompt tool lets you check the storage drive for errors, which may be the cause of the unmountable boot volume message.
Follow the above steps again to open a Command Prompt from the recovery menu, then enter the following command:
chkdsk /r c:
The /r flag locates any bad sectors on your disk and fixes those errors. If you don’t include this, Chkdsk will simply report errors it finds. You need to include c: so the operation scans your Windows partition (the most common location for it). Replace c: with d: or another letter if you’ve moved yours somewhere else.
Chkdsk may tell you that the volume is already in use, and ask you to run it next time the system restarts. If it does, enter Y for yes and reboot to start the process.
This can take some time, so you may have to wait a bit. Once it’s done, reboot again and see if the boot volume issue has cleared up.
Step 6: Try an SFC Scan
For the final Command Prompt solution, you can try another important utility. SFC, or System File Checker, looks for corrupted Windows system files and attempts to fix them. If nothing above has fixed your issue, this is worth a try.
Open a Command Prompt on your recovery drive again, then enter the following command:
sfc /scannow
Wait until the process completes; it will tell you if it fixed anything. Like the other commands, after it completes, you should reboot and try to load into Windows again.
Are you Still Having an Unmountable Boot Volume? Test Hardware and Reinstall
If you’ve completed these troubleshooting steps and continue to see an unmountable boot volume error every time you boot, your problem is deeper. There are two further solutions to try.
First, you may have a hardware issue. Your hard disk drive or solid-state drive could be corrupted, dying, or suffering from a faulty connection. If you’re confident, open your computer (which is easier on a desktop than a laptop) and check to make sure the drive’s cables are all securely connected. Sometimes faulty RAM can also cause this problem, so make sure the RAM is properly seated.
If you check the connections and everything looks OK, you should run some Windows diagnostic tests to determine if a component is dying. Replacing it should fix your issue, but you’ll need to talk to an experienced computer technician if you can’t swap the components out yourself.
Image Source: MakeUseOf
After ruling out hardware, your Windows installation may be corrupted in a way that the above utilities can’t repair. In that case, your only option is to reinstall Windows and hopefully fix the problem by starting fresh.
This is a pain and takes time, but it isn’t as tedious if you have a backup. You may want to first run through other potential fixes when Windows won’t boot before taking this intensive step.
Conclusion
Fixing an unmountable boot volume error in Windows is achievable using various methods discussed in this article.
It’s essential to understand the causes and take necessary precautions before attempting any fixes. By following the step-by-step guides provided, users can resolve this issue and restore their system’s functionality.