The Authentication Portal uses a Token Based authentication. If multiple users use the same computer, then the token will be overwritten every time the users change.
This can be annoying, because you then must login every time. To help with this you can tell the Totalview Client to name the token something else, so there is no conflict.
Create a shortcut to the Totalview client and add the argument /u:[UserName]. The UserName is the same you would use to login to Totalview
Verify that it works
You can verify that this works by looking up your tokens on your computer by going to %appdata%\Totalview
There should be at least 2 token if you are running with this argument in the shortcut. The default token called totalviewaccess.token and then the [username]totalviewaccess.token.