Mitsubishi GX Developer FX

Does anyone know the name of the windows service I need to stop in order to free up my com port. I need to switch back and forth from programming to my hmi software (non-mitsu)

Other than RSLinx I've never seen a conflict with GX-Developer. I would reccomend going to Device Manager and seeing what else is using your com port. I've also had good luck with most USB to serial adapters using GX Developer, Is this an option?

as far as i know there is no simple way to tell what software is using com port. if you only have serial port and you try to use it both for plc and hmi programming but have no pass through connection configured, you will have to go offline or close port (or application) that uses port before you can use another one. some applications like to monopolize com port and some of them can be easily tamed (like rslinx), others not so (like activesync etc.).

You have to go offline from gx to program/upload hmi soft then back online to switch between the two.

It is called VLINKS you should see it in your list of running processes in task manager.

Marc