If you download and install ARC500 for the free trial period, there is a USB cable driver installer which works with my Radio Shack 20-546 cables. Go to the Scanner tab and click on Install USB Driver.
Here is a copy of the original driver that came with the PSR-500 scanner. It works fine up to at least Windows 8.1. At times, Windows changes something or plugging the cable into a different USB port changes something and the driver has to be reinstalled.
I would try reinstalling the driver. For some reason, I have to reinstall the driver once in a while due to the Windows operating system changing something which makes the driver stop working.
I would try reinstalling the driver. For some reason, I have to reinstall the driver once in a while due to the Windows operating system changing something which makes the driver stop working.