Vcenter troubleshooting

Hi gurus

More help needed

1) When I open Vcenter web client I get the following errors

                  a) client is not authenticated to VMware Inventory service ( attachment)

                  b) Unable to create the managed object (attachment)

  I have tried the following

     a) Restart the Inventory Service (no avail)

     b) Restart the Vcenter server (no avail)

     c)  Vmware KB 2033620 ( no avail and some errors)

           1) error

                  "Using C:\Program Files\VMware\Infrastructure\Inventory Service

                  VMware vCenter Inventory Service

                  Inventory Service already stopped.

                  Intializing registration provider...

                  Getting SSL certificates for https://server FQDN:XXXX/lookupservice/sdk

          Unexpected status code: 404

          Unexpected status code: 404

          Return code is: ServiceNotResponding

          2

          Error 2 registering with https://serverFQDN:XXXX/lookupservice/sdk. Cannot continue.

          2"

  so at this point I need some serious help to get this fix

     1) how do I go and check if the sso instance is on my local machine ( i did not setup this Vcenter) but there has to be a way to find this out, if the          instance is local or where is it pointing to.

      2) what else could be happening with this two errors and if someone has an idea.

Thanks a bunch gurus