It seems like the “Prolific USB to Serial” driver was not installed properly, which is why you are getting this PL2303not working error.
To fix this issue, what you need to do is, right-click on that in the “Device Manager” and do the uninstall if the option is available, if you do not get this option then leave it. Afterwards, download and install the driver that I’m giving you here below.
Here’s the Prolific PL2303 Driver Download Link
If this doesn’t work then try this driver updater, it’s free.
Do let me know if this doesn’t work.