How to Fix VMware Error “Module Disk Power on Failed”

The Module Disk Power on Failed error message appears when you are trying to boot up a virtual machine using any VMware software. This error message usually reflects towards the virtual machine not being powered off safely or properly which as a result generates the said error message. Along with the said issue comes the “The process cannot access the file because another process has locked a portion of the file” which throws more light on what the issue is. Basically, what is essentially happening is the virtual machine that you are trying to power on is blocked by other VMware files. Thus, due to this lockage, the virtual machine does not boot up successfully.

Module Disk Power On Failed

Why does this happen? This can happen when you have a sudden power cut or your virtual machine is not powered off. Not just that, as it turns out, in some cases the issue can also be generated after your virtual machine crashes and you try to power it back on. The question that arises in mind is why is the virtual machine blocked or locked? To shed light on this, let us have a more detailed look at how VMware virtual machines work, and then we’ll proceed with the solution to the error.

VMware Lock Files

When you start a VMware virtual machine, there are certain files created that ensure that no other VMware process is able to access the said virtual machine. This is done through the help of .lck files that are created in the same directory as the virtual machine. The main reason why these files are created is that they prevent multiple virtual machines from reading and writing to the disk. If these files weren’t there, then, as we mentioned, data corruption could be caused due to various virtual machines reading and writing to the disk.


Therefore, the presence of a lock file basically amplifies the fact that the said virtual machine is powered on. These files are automatically deleted when you power off the machine so that you face no issues the next time you power on the machine. However, in case the machine crashes or is not powered off correctly, VMware might not be able to remove the lock files and as a result, a stale lock remains. When you power on the virtual machine that has a stale lock, VMware tries to remove the file by checking two conditions that basically see if the lock was created by the same host and whether the process that created the lock is running or not.

An error, as in this case, is thrown when either of these conditions is not true and the VMware is not able to remove the lock file. In such a scenario, what you have to do is manually delete the lock files yourself and you should be good to go.

Manually Delete VMware Lock Files

As it turns out, you simply need to delete the lock files that are preventing you from booting up the virtual machine. As we have mentioned above, these files exist in the same directory as the virtual machine and deleting them just takes a few simple easy steps. Follow through the steps given down below to remove them:

  1. First of all, make sure that your virtual machine is powered off. If it isn’t, power it off by right-clicking the virtual machine and navigate to Power > Power Off.
  2. Once you have done that, we’ll have to make our way to the directory where the virtual machine resides. To do this, right-click on the virtual machine again and click the Open VM directory option.
    Opening Virtual Machine Directory
  3. This shall take you to the directory where the virtual machine exists while also saving you the hassle of looking for it manually through Windows Explorer.
  4. Inside the directory, delete the folders that end with the .lck extension. You can also, alternatively, simply rename them to something else or move them from that destination to somewhere else.
    VMware Lock Files
  5. Once you have done that, open up VMware again and then try powering on the virtual machine.
  6. Your virtual machine should now power on without any issues.

Muhammad Zubyan

Muhammad Zubyan is a certified Google IT Support Professional with over 7 years of extensive experience. He has worked on more than 1500 computers, gaining valuable insights that enable him to detect and troubleshoot any complicated root cause of Windows-related issues and errors. In addition to managing Appuals as a Senior Editor, he is currently developing his own Game Optimization program that caters to both gamers and casual users alike.