Hyper V General access denied error
IDE/ATAPI Account does not have sufficient privilege to open attachment 'E:\VMs\VMName\Disk0.vhd. Error: 'General access denied error'
What this is trying to tell you is that HYPER-V has a user account for each VM. This user account is a random string of letters & numbers. This user account is hidden. This user account has access to the the VHD's.
If you were to do something like move the VHD's off the drive, expand the drive and move them back on the new drive, the user account would no longer have access.
No problem. Just add the permissions back in.
Looke at the details of the error message and it will let you know the user account name. Something like:
AE78918D-FE0E-4E6D-AFF5-25B32D4FE243
In command prompt (as admin), type something like:
C:\>icacls "F:\VHD\VHD-NAME-HERE.avhdx" /grant "NT VIRTUAL MACHINE\AE78918D-FE0E-4E6D-AFF5-25B32D4FE243":(F)
It will repsond with something like:
processed file: F:\VHD\VHD-NAME-HERE_756DFD7E-5E29-4ABA-B12F-40BAD636E2A2.avhdx
Successfully processed 1 files; Failed processing 0 files
Now start the VM and it should start without hassle.
NOTES: