Could you please open up a SQL server management studio and connect to the the vCenter Server DB. Select the vCenter DB instance and run the query "select * from vpx_access". If you do not see the user name, which you are using to log-in to vSphere Client run the query to add a user to vpx_access table.
insert into vpx_access (ID, PRINCIPAL, ROLE_ID, ENTITY_ID, FLAG) values ('100', 'ACME\JSMITH', '-1', '1', '1');
To commit the changes run the following command: commit;