Prolific legacy USB chip driver issues¶

Overview¶

The short story is: lots of counterfeit Prolific USB adapter chips were created and flooded the market. Prolific decided to strike back by discontinuing their most popular product and releasing a new driver that just does not work at all. Since Windows tries to always update to the latest version of any driver, users get the new driver installed regularly which intentionally does not work at all.

This manifests itself as a non-functioning serial port visible in Device Manager, with a message from Prolific indicating they have successfully disabled your device:

Note that all the other ports have names (like COM1, COM6, etc) but the Prolific devices do not.

Workaround¶

Installing the older version of the driver from before Prolific poisoned the well still works at least as of Windows 11. It is a constant battle with Windows, which will keep trying to update the driver regularly, but at least it is still possible in order to keep using these devices.

You can get the old driver (3.2.0.0 from 2007) and some instructions at miklor.com. If you indeed have a counterfeit device (which will be almost everyone arriving here) this is your only option with the current hardware.

If you have a genuine Prolific device that has been abandoned, you may want to try the pl2303-legacy tool, which can help install and maintain the latest-supported version of the driver for your device.

Solution¶

The real solution is to buy all new cables. It is definitely recommended to avoid Prolific devices, especially since this could happen again and Prolific could decide to pull such a stunt in the future. In all cases, choosing a genuine FTDI-based device is the suggested path. CHIRP project supporter BlueMax49ers sells genuine FTDI-based cables for almost any radio on the market and would be a good place to start.

Both Microsoft and Prolific have contributed to this retroactive disabling of your device, even though you did nothing wrong. You might consider sending them feedback about the situation and/or voting with your wallet in the future.