We used to have a Portserver TS 2 port, but we uninstalled it and put in a Portserver TS 4 port instead. I’ve noticed that we cannot select COM ports 6-19. Only 2,3,4,5 and 20+ are available. Are there any possible reasons why 6-19 cannot be selected?
Sounds like you are running into Phantom Ports. The below link describes how to remove them from your system:
Thanks! Cleaning the keys in the registry for the non-standard ports did it.