Edit VideoServer object and Learn button is greyed out.
CyberStation 1.94 Video
The Learn key in the CyberStation Security editor under VideoServer had been changed to a 'lock'.
The Learn key in the CyberStation Security editor under VideoServer had to be changed to a 'key' for user Group 128.
Note: there is an unconfirmed possibility that this occurred as a result of an upgrade, as the Admin user was using Group 128 and typically a change to user security during an upgrade would default to a 'key' for Group 1 but a 'lock' for all other security groups.