Unable to access newly setup vCenter 5.5 using client

Hi all,

I have just finish setting up the vCenter successfully but i'm unable to access it via the client with the error message below.

Error: You do not have permission to login the server: VC Hostname

The accounts I have try are the domain admin, service account for the vCenter and my account. All these account have administrator access to the vCenter server itself.

I also add these accounts using Web Client to Administration -> SSO -> User and Groups -> Groups -> Administrator.

So far I'm only able to access the web client using vsphere administrator. Anywhere else I may miss out ?