Hi Björn, welcome to the forum.
If you authenticate with a display computer, then the computer that sends the authenticate command becomes the master, and the production software is locked
From Watchout Manual:
To control a WATCHOUT display cluster via the network, connect to TCP/IP port number 3039 of one
of the WATCHOUT display computers. The computer with which you initiate communication becomes
the master of the cluster, and will automatically control the other cluster members,
Unlike UDP, TCP holds a permanent connection, so if you send the authenticate command, there is a connection between V-Control and Watchout Display computer.
In V-Control a TCP channel is automatically opened when the project file is loaded. This is necessary because usually the channel needs to be open to control the device. There is no way to change this behavior at the moment.
What you can try is to send the authenticate command just before the PowerDown command. In this case V-Control is authenticated just for PowerDown.
If that doesn’t work because Watchout Display Software accepts only one TCP connection, there is another work around.
You can use V-ControlRemotePC and install it on the Display Computer.
and here is a Topic how to use it in your case
Another solution is to use a batch file and execute this with the ShellExecuteAsFunction command. Here is an HowTo: