Everything solved.
I need to use the same ip in T50 and on a remote PC because I don’t have the original source codes I can’t know how the VNC server is configured
It happens that if I put different ip addresses in T50 and remote PC, alarm appears in the third-party SCADA (allen bradley) with third-party OPC server also (schneider), the alarm in the SCADA arises because you understand that the T50 panel is not connected, I solve this by integrating everything in a switch (remote pc, T50 and PLC) in this case everything is connected the alarm does not appear but on the remote PC I can manipulate all the variables except the on and off of the computer that are long pulsation variables for more than 5 seconds, all the other variables work except those of on and off.
I guess this can only be corrected if I had the iriginal codes, but I don’t have them.
At the moment it works for me this way because the utility is not to work with remote PC and t50 at the same time, it is only for when t50 panel is unusable then to be able to work with remote PC by disconnecting the panel.
Any other suggestions would be very welcome. At the moment I’m still with the same thing. Thank you all.