While executing verify , Getting "Failed to execute createHOMObj for the Setup : Error on Connection to host (vCenter IP)"

While Executing NAS tests , as a prerequisite , I need to run verify. While Verify runs , I am getting following error:

" ERROR: Trouble creating test instance, Failed to execute processSetup for the Setup : Failed to execute createHOMObj for the Setup : Error on Connection to host (vCenter IP address)".

Is it mandatory to give username and password of vCenter windows vm as  "username:  administrator & password: vmwareesx" ?

Regards