Ethernet

How to fix Ethernet problems after a recent Mac security update

As my colleague Christian reported on Saturday, some Mac models have been plagued by non-working Ethernet ports after installing a new security update outed by Apple. Although a lot of modern Macs don’t even have an Ethernet port, many models still carry it and many people still love using a wired internet connection because it’s faster, more reliable, and more secure than a wireless network.

The security update, known as “031-51913 Incompatible Kernel Extension Configuration Data 3.28.1,” reportedly blacklists the Broadcom BCM5701 driver used by the Ethernet port that comes standard on many Mac machines.

Fortunately, there’s a light at the end of the tunnel for anyone experiencing issues with their Ethernet ports after installing this security update. Apple has issued a support document on Sunday that notes how to fix the problem. In this tutorial, we’ll go over the steps to fix the problem yourself.

Recent OS X security update has disabled Ethernet port on some iMacs and MacBook Pros

In squashing software bugs, you inevitably introduce new ones—that’s a fact of life. According to a thread on Reddit, Apple’s recent OS X security update has inadvertently disabled the Ethernet port for some owners of Apple’s all-in-one desktop and the MacBook Pro notebook.

Making matter worse is the fact that Apple pushed this security update via the silent updating mechanism, according to a poster on Reddit who probably enabled the option in System Preferences → App Store that prompts OS X to automatically install system data files and security updates.