Fix Error: Acronis Unable to Lock The Disk
This article will show you how to fix the Acronis unable to lock the disk error, and introduce the best Acronis alternative for error-free disk or system cloning.
Last Updated July 1, 2025
Acronis Clone Failed: Unable to Lock The Disk
I'm trying to clone my HDD disk to my new SSD drive using an Acronis bootable USB drive. But I ran into the problem below when I boot from the flash drive:
"Unable to lock the disk. Boot your computer from a Linux-based bootable media, and then try again."
Why would this happen? How can I resolve the Acronis unable to lock the disk error?
So, you are trying to clone your hard drive using Acronis True Image and suddenly encounter the error message - "Unable to lock the disk." It would be frustrating, whether you're looking to back up the disk or upgrade to a new SSD. But don't worry. This lock error means that Acronis cannot gain access to the disk.
This guide dives deep into how to fix the Acronis True Image unable to lock the disk problem step by step. And we'll also show you a better, headache-free alternative to Acronis for disk or system clone.
How to Fix Acronis Unable to Lock The Disk
There are many reasons that would cause Acronis clone failed like incorrect drive connection, software conflicts, and Acronis lack of proper administrative privileges. Here, the Acronis failed to lock the disk problem was due to not performing a full shutdown prior to entering the Acronis rescue media environment. Please follow the guidelines below to get rid of unable to lock the disk on Acronis:
👉You can force a full shutdown by holding down the Shift key when clicking on Shutdown, then restarting the system to launch the rescue environment.
👉You can also remove the original HDD from the PC and replace it with a new drive so that no formatting occurs on the new drive to send out a lock flag.
👉Sometimes, fast startup and hibernation use the hiberfil.sys file, which keeps the disk in a semi-active state, causing the Acronis unable to lock the disk error. To disable them: Open Command Prompt as admin > Type powercfg.exe /hibernate off and press Enter to turn off the hibernation. Then, go to Control Panel > Power Options > Choose what the power buttons do, and uncheck Turn on fast startup to disable fast startup.
👉Antivirus programs often monitor system drives in real-time, which prevents Acronis from locking the disk. Temporarily disable your antivirus software before initiating the clone. Just remember to turn it back on afterward.
Try Acronis Alternative for Error-Free Disk/System Clone - AOMEI Cloner
If Acronis keeps letting you down, AOMEI Cloner is a clean, simple, and powerful cloning alternative solution. It handles system and disk cloning with ease. Check out its significant features below:
- Disk Clone & System Clone: Easily migrate only your OS or the entire system drive, including operating system, installed applications, and all other data, to a new drive without reinstalling, and ensure booting up securely after cloning.
- Hot Clone: This software allows you to clone a running system without restarting or interrupting your current work, which means zero downtime.
- Intelligent Clone: Copy only the used space, making the process quicker and allowing cloning from larger drive to smaller drive.
- SSD Alignment: Optimize partition layout for peak SSD performance and lifespan.
- Bootable Media Creation: Support to create a WinPE USB or CD/DVD to perform offline cloning if needed.
100% SecureThis tool is compatible with a wide range of Windows operating systems, including Windows 11, 10, 8, 7, XP, Vista, and all Windows Server systems. Here is how to run AOMEI Cloner for disk cloning if you want to completely get rid of the Acronis True Image failed to lock the disk problem!
Step 1. Plug in the new SSD or HDD, and make sure it is detectable. If it's external, use a SATA-to-USB adapter.
Step 2. Download and launch AOMEI Cloner, click on Clone in the left panel, then choose Disk Clone to copy the entire drive, or System Clone if you just want to move Windows to another drive.
Step 3. Pick the system drive (usually Disk 0) that you want to clone.
Step 4. Choose your new SSD or HDD as the destination drive. Please note that everything on it will be overwritten, so back it up if needed.
Step 5. Check the SSD Alignment box to improve SSD performance if you're cloning to an SSD. Then, click on Start Clone.
- Useful Tips:
- If your target drive is smaller than the source drive, DO NOT check Sector By Sector Clone. This feature will clone all sectors on the source drive(whether they are used or not), which may cause the clone to fail.
- You can also use the Edit Partitions function to adjust the partition size and partition style of the destination disk.
To boot your computer from the cloned drive, you can restart the computer > enter BIOS or UEFI settings. Then navigate to the Boot section and set the cloned disk as the first boot option. Or, you can replace the old drive with the newly cloned one directly.
Conclusion
As an Acronis user, you may encounter a variety of cloning failures or stuck issues. There can be many reasons for these problems, and there may be different solutions for different situations. In addition to spending a lot of time and effort to find a solution, we highly recommend AOMEI Cloner as it can easily clone your disks, supporting a wide variety of HDDs and SSDs. In addition, as a powerful cloning software, you can also use it for system cloning and partition cloning.