Cannot start Virtual Machine after Hard Disk resize: 'Unable to connect to Hard Disk 1'

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I cannot start Windows Virtual Machine after resizing its Hard Disk

Error message:

    "Unable to connect to Hard disk 1. No operating system Installed on this Virtual Machine."


In order to check the Virtual Hard Disk you will need a second Virtual Machine.

NOTE: To create new Virtual Machine please refer to this article: How to install Windows virtual machine on Mac using Parallels Desktop?

Note: We would strongly recommend to backup your original Virtual Machine before performing the steps below.

Once the second Virtual Machine is installed please follow the steps below:

  1. Start the Second Virtual Machine (VM 2), install Parallels Tools (in the menu bar go to Virtual machine > Install Parallels Tools)
  2. Shut down VM 2, go to the Configuration of VM2 > Hardware and click '+'
  3. Add the Hard Disk from original Virtual Machine (VM 1) (the one that has been corrupted)
  4. Switch to Boot Order and uncheck second (that you've just added) Hard Disk 2:

  5. Start VM 2
  6. Download Test Disk (.zip file) from to VM 2
  7. Unzip file to the Desktop of VM 2
  8. Open the resulting testdisk folder and launch Test Disk application (testdisk-win.exe)

  9. Create new log file

  10. Choose the disk partition that has been connected

  11. Choose the type of partition (for Windows Virtual machines choose "Intel")

  12. Analyse the partition

  13. Choose 'Quick search'

  14. choose 'Write' to write the boot sector of partition
  15. quit Test Disk

  16. shut down VM 2
  17. Go to the Configuration > Hardware of VM 2 and disconnect Hard Disk that has been added (choose Hard Disk 2 and click on '-')
  18. Start your original Virtual Machine and install Parallels Tools

For more details on working with TestDisk utility please visit its Documentation at and Step-by-Step guide

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