You might get following error after you move or replace a virtual disk drive file of a hyper-v virtual machine.

An error occurred while attempting to start the selected virtual machine(s).
‘TestVM’ failed to start.
Microsoft Emulated IDE Controller (Instance ID
{83F8638B-8DCA-4152-9EDA-2CA8B33039B4}): Failed to Power on with Error ‘General
access denied error’
IDE/ATAPI Account does not have sufficient privilege to open attachment
‘D:\VM\TestVM\TestVM.vhd. Error: ‘General access denied error’
Account does not have sufficient privilege to open attachment
‘D:\VM\TestVM\TestVM.vhd. Error: ‘General access denied error’

This is because the permissions on the new virtual hard drive (D:\VM\TestVM\TestVM.vhd in this case) are incorrect. Here is the steps to fix this permission file.

1. Open Hyper-V manager, Right click settings of the virtual machine,
2. Find the Virtual Hard Drive and choose "Remove".
3. Re-add the same Virtual Hard Drive back to the machine.
4. Now start the VM again, it should boot successfully.