vCenter 5.1 Single Sign On Failure to Authenticate Active Directory Users

After a painstaking few months with the fairly buggy release of vCenter 5.1 and new counterpart module called Single Sign On (how did this ever get past QA I will never know), there is finally light at the end of the tunnel.

If you were having trouble adding active directory users or groups via the vSphere client to manage your hosts via vCenter, it is likely you face the same issue with single sign on (SSO).