When trying to add a machine to a catalog, an UUID error occurs. The following are the logs:

"Task Information: Failed Requested machine count: 3 AD account action: Create accounts Successful accounts: 3 Successful machines: 0 Machine Failures: S-1-5-21-1666584124-XXXXXXX-XXXXXXXXXX-XXXX: Failed to create the virtual machine; S-1-5-21-1666584124-XXXXXXXXX-XXXXXXXXXX-XXXX. Inner Error: Failure in CreateClone, UUID_INVALID, VDI, 9c160fa8-8c94-4035-XXXXXXXXXXXXXXXXX ErrorID : Citrix.ManagedMachineAPI.ManagedMachineException TaskErrorInformation : Citrix.ManagedMachineAPI.ManagedMachineException: Failure in CreateClone, UUID_INVALID, VDI, 9c160fa8-8c94-4035-XXXXXXXXXXXXXXXXX ---> Citrix.ManagedMachineAPI.ManagedMachineException: Failure in CreateClone, UUID_INVALID, VDI, 9c160fa8-8c94-4035-XXXXXXXXXXXXXXXXX ---> XenAPI.Failure: The uuid you supplied was invalid. at XenAPI.Response`1.parse() at XenAPI.VDI.get_by_uuid(Session session, String _uuid) at............................."

As the Base Disk has been removed/deleted, the Catalog will not know the UUID attached to the machine to create new ones.

A new Machine Catalog will need to be created to resolve this issue.