@world101 said in Silicon labs CP210x driver not working on my Mac with Catalina OS( version 10.15.4): (i.e. "flip it over") if the driver doesn't seem to detect the device). (i.e. "flip it over") if the driver doesn't seem to detect the device) <= in my case the Mac doesn't even see the Siliconlabs driver as being present. How do I "direct email you Sir ?