When attempting to login I receive the error message, "username or email is incorrect".
ThinkTank offers two options for joining a session: Account Holder and Guest.
If you've never logged into ThinkTank before, you may need to login as a guest. The guest login is found in the center of the screen, and does not require a username or password.
If you've been provided with a username and password (note: not the same as a passkey to join a session), then login as an account holder. The account holder login is at the top of the screen.
If you're uncertain how you should login, contact the session leader that provided you with the invitation.