Diag user account is locked if you get the error message when trying to login to Systemshell: Unable to launch systemshell because the 'diag' user is locked. This KB article covers how to unlock diag ...Diag user account is locked if you get the error message when trying to login to Systemshell: Unable to launch systemshell because the 'diag' user is locked. This KB article covers how to unlock diag user account.