Renoir

Not the most elegant solution but it works. 1 machine on the network is able to query the c drive of all the other users and it tries to open a file in a set directory. If the user is on the system that file is open for exclusive use. Therefore my attempt to open it will bring up an error which I trap. Red lights are shown against users are are in the system, green lights against users whoose machines are of or are out of the system.

All the staff do is push a button on their screens

Colin