If your computer doesn’t have an Ethernet port, try using a USB to Ethernet adapter, or a Thunderbolt to Gigabit Ethernet adapter. A recent background update from Apple might disable the ethernet port on some Macs. If you aren’t sure what to enter, check with your network administrator or ISP. Apple issues a fix for ethernet disabled by a recent OS X update Here's how to get your ethernet working again if it was affected by Incompatible Kernel Extension Configuration Data 3.28.1. Uninstall the dozens of other drivers you may have installed in the process of trying to get this working. In many cases, you’ll automatically connect to the internet. Surely all the 3rd party adapters available on eBay are guaranteed to be functional. Unplug your USB adapter, and reboot and give yourself a clean slate. Here are some instructions on how to fix it. If not, complete the following steps to enter your network settings. Update: This trick also works with macOS High Sierra. If you bought a cheap USB 2.0 to Ethernet adapter for your MacBook Air or MacBook Pro 13 inch 2015, then you know the simple plug and play does not work. Reboot. AX88179 USB Ethernet and MacOS 10.13 High Sierra When I purchased the new Macbook Pro last year, one big issue was the lack of widely used interface ports. Steps to get your adapter working if you've never used the adapter before in Mac OS 10.11 El Capitan.