Thanks for posting your question here. We’ll be happy to help. First, reboot your mac to be sure all of the USB ports are active. Macs sometimes disable USB ports until the next reboot if there’s been problems. Next, if it’s still not showing up, I’d like you to try moving the USB to Serial adapter to a different USB port.
Following the directions here:
Can you say what happens when the installer finishes? Does it report any errors or do you get the “Installation Sucessfull” message?
The following command is actually looking for the prolific driver, so it should read:
kextstat | grep prolific
Double check that you have it correct.
Then run the
ioreg -c IOSerialBSDClient | grep usb
You should see the device. if you’re not able to see it at that point, is it possible to test the device in another machine? Also verify that the USB port on the Mac is functional by testing it with a simple USB device like a mouse.
Thanks for your patience,
Let us know how it goes, and we’ll figure out next steps,