I recently made a change to a VM that I wanted to roll back but I didn’t have a snapshot. So I turned the VM off, renamed the old vhd, and copied a recent backup from another machine. When I went to start the VM I was greeted with an access denied and the following event in the Hyper-V event log:
‘Win7Seqx86’: IDE/ATAPI Account does not have sufficient privilege to open attachment ‘H:\VM\Win7Seqx86\Win7Seqx86.vhd’. Error: ‘General access denied error’ (0x80070005). (Virtual machine ID ECA0BD63-76CE-4C5E-96AB-44F0D635CBB3)