I have to provide the exact error message on Monday. It was too late in the day and I was ready to go home.
The error message occurred after completion of the steps, but at the 90% mark while adding the host.
As far as the hypervisor is concerned, I do believe that it is a very limited version of vSphere, because when I checked the features of the host, I noticed that it had only two features:
1. 8 CPUs
2. SMP
I think you are on to something, I will attempt to add one of our vSphere ESXi Standard hosts to vCenter.