PL2303HXA PHASED OUT SINCE 2012. PLEASE CONTACT YOUR SUPPLIER
If you are seeing this issue, you can resolve the problem by downloading and replacing the Windows driver with this one using Device Manager. In my case this was trying to use a USB to Serial (RS232) adapter which just wasn’t working. https://github.com/brucetsao/Drivers/raw/master/FAKE_PL2303/IO-Cable_PL-2303_Drivers-Generic_Windows_PL2303_Prolific.zip Connectix.nl provide a more detailed overview of the solution here.
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