Symptoms

Parallels Desktop displays one of the following error messages when you try to start your virtual machine:

    There's not enough disk space available to start the Windows 10 virtual machine.

    Free at least XX MB on the hard disk that stores the "Windows 10" virtual machine and try again.

Cause

The errors above mean you are running out of free space on your host Mac OS X hard drive.

Resolution

1. Find how much space is left on your Mac hard drive:

   • Run Disk Utility > check Available (Purgeable + Free) amount of free disk space:

     

   • Or go to Apple menu > About This Mac > Storage:

     

     

2. Free up space on your Mac hard drive by moving unnecessary files to the Trash and emptying the Trash. To find out more about disk usage and file and folder sizes, you can use a third-party application such as Disk Inventory X (free application released under the GPL). Visit KB123553 for more details.

   NOTE: You need free disk space at least equal to the amount of memory allocated to the Virtual Machine. Go to your virtual machine's Configuration > Hardware > CPU & Memory.

3. Run First Aid from Recovery to find and repair possible errors within the disk file system by following the instructions from the article.
4. Optional: You may also want to check and delete snapshots of your virtual machine. See KB #122390 for details.