Summary: Use Windows PowerShell to add a new hard disk drive to a virtual machine on Hyper-V.
How can I to add another hard drive to my virtual machine?
Use the Add-VMHardDiskDrive cmdlet with the following command:
STOP-VM -vmname "My Virtual Machine"
NEW-VHD -Dynamic C:\VHD\MyDrive.vhdx -SizeBytes 60GB
ADD-VMHardDiskDrive -vmname "My Virtual Machine" -path C:\VHD\MyDrive.VHDX
START-VM -vmname "My Virtual Machine"