virtual server has lost trust relationship inside virtual server that has own DC

We have a Microsoft Windows 2008R server with hyperV that has a couple of virtual servers on it.  It has it's own domain and one of the virtual servers is a domain controller. Another of the virtual servers is an Exchange 2010 box which has worked well.

We had decommissioned the exchange server because we were bought by another company and have gone on their domain and exchange server.

However, the box is sitting there and was OK when we disconnected it from the network.  I was trying to get on the Exchange server the other day to get off some information that I needed.  I brought it up and it wasn't responding properly so I stopped and started it.  When I did, the Informaiton Store just said STARTING and wouldn't go to STARTED.  I had another image of the exchange server, so I reverted to the prior image.

When the Exchange server came back up, it said that the "trust relationship between the workstation and the primary domain failed".

I logged back on and it allowed me to log on as administrator of the machine, but not as administrator of the domain.

Do I just follow the same steps I would take as if this was a PC to regain trust?  Or do the steps have to be different because it is a virutal server?

Here are the steps I would use:

Delete the offending Computer Account that resides in Active Directory.
Delete the Computer’s IP Lease(s) in DHCP
On the client:  Log onto the local machine (not the Domain) as an Admin.
Unjoin the Domain by joining a “TEMP” workgroup.
Reboot
Log into TEMP workgroup as the Admin.
Rename the Computer.
Reboot
Log into the Local Machine, now rejoin the Domain.
Reboot
Login into the Domain.
Rename the Computer back to what I originally wanted.
Reboot