Port Access Denied Issue - QST-Lab TCS Serial Out Component

I have seen similar posts before but none of the proposed advice has helped me so far I’m afraid. Does anyone have any ideas how this error keeps occurring:
Error initializing TCS Device: could not open port ‘COM4’: PermissionError(13, ‘Access Denied’, None, 5)

I’m trying to control my QST.Lab (TCS II) device through PsychoPy so that I can later implement it into our experiment. I have already tried plenty of steps:

  • adjusting all port settings to fit (same timeout/baud rate/port name etc.) in all places (the Python-script module file supplied by the developers, in my custom code, in builder and in the device manager’s port settings)
  • only ever having one PsychoPy Experiment open
  • restarting the program/computer
  • giving exemptions in firewall settings
  • reassigning port number to a much higher number
  • updating all drivers, all software (including PsychoPy, the device’s and the port’s, drivers)
  • running PsychoPy as an administrator

I know that others have made it work before but they seemed to have been able to successfully resolve their issues with one or multiple of these steps.

I have been able to control the QST.Lab through pure Python programming scripts in Spyder, so I doubt this issue is due to faulty hardware. However, my research team would prefer if I were able to avoid rewriting the entire experiment to run as a Python script because we have been very happy with PsychoPy so far.

Any help would be greatly appreciated!

Issue resolved

I simply removed the serial port component from Builder view, handling everything through the custom code component instead, which worked.