Only the the supervisor account and or Active Directory users who were select during the initial install of MCU (Management Console for Unix) can login to the console.
Other users have not yet been configured to login.
From within MCU navigate to the Systems settings by clicking on the gear shaped icon in the top right hand corner.
From within Systems Settings select "Console Roles and Permissions".
There are several different console roles to choose from depending on what privileges you would like different users to have.
Select a role and click the Members button on the right hand side. From the dialog box that opens you can add or remove users.