Ok I downloaded ver 06.12.05 and I get the same error message about not being able to open the port. Any ideas?[/URL]
Plug in the cable, open the software, connect to the radio, turn the radio on, click on File and then Read Device. It should give you a little window with a drop-down which will have you select the Com Port. Once you have done that, it should read the radio.
That usually solves the problem. You have to do it in that order without skipping a step or taking any other shortcuts.
One other thing, when you install 6.12.05, be sure that it removes the older version OR when you fire it up, be double sure you have the newer version running (if you want to keep the older version on your computer.)
I think you already mentioned it, but you should have the latest Prolific driver set installed as well. I found that it worked best for me when I removed all the USB drivers on my machine and then installed the Prolific set.
Are you using a USB cable or a USB to Serial adapter and a Serial cable?