Windows Serve 2008 R2. Not Activate Server if you have a VM

I have a VM with Windows Server 2008 R2.

If you delete the machine, and you copy de .vhd file you need to activate again the machine.

You need VMM08 or Export the VM with the Hyper-V MMC.

When you export the VM, you save everything and you save inside the folder:
a config.xml file
a .reg file.
You can edit these files, and rename the options. So you can use like a template to import new machines inside your HYper-V and you dont need activate the Windows Server 2008 R2.