Hi,
Before I tried it, I did a recovery of the OS from a point at which vCentre had been removed. Re-installed vCentre and then added the hosts back into it. There were a couple of warnings with the invetory service as it detected that it was once installed, but it ended up working. Disconnected the hosts and removed them from the inventory.
We are now creating a new VM on an unmanaged box using the Appliance instead as we had non stop problems trying to use the install on a windows box.
Thanks for the help.