This error message is displayed while attempting to remotely run workshop.
Make sure workshop is no longer running.
In the telnet/rlogin session window, type: /bin/ps -ef | grep ttsession. If one is running in the system that belongs to the telnet user, type kill pid_of_ttsession.
In the telnet rlogin session, type /usr/dt/bin/ttsession -s -d machine_telnetting_from:0.0.
Start workshop.