Error 25085.Setup failed to register VMware vSphere Update Manager extension to VMware vCenter Server

Hello All,

I am facing this error during vSphere Update Manager installation although I did tried some resolutions posted on VMware KB, like:

VMware KB: Installing VMware Update Manager fails with the error: Error 25085

and this:

http://kb.vmware.com/selfservice/microsites/search.do?language=en_US&cmd=displayKC&externalId=1036055

I input the user administrator@vsphere.local in the Update Manager installation to connect to vCenter Server. Therefore, this user already has administrator role with 'Register Extention' permission included.

However, after doing all the above, the error still remains. Is there anyone have another resolution to solve this error?

Thanks in advance.