Don’t be embarrassed if you have no idea what it is; after all, Apple doesn’t even include an ethernet port on its laptops anymore. For the uninitiated, it’s a network connection type that involves using an actual cable. On the desktop, though, Apple still includes an ethernet port. Recently, Apple issued a minor kernel extension update for OS X, but the update had a bug that disabled ethernet. Apple fixed the offending update, but if you installed the update and still see problems, Apple has a support article for. If you have an ethernet and Wi-Fi working at the same time, you may not have noticed your ethernet connection not working.

Formatting a drive will erase all data and partitions on the disk: Connect the hard drive or USB key to the Mac. Launch Disk Utility, located in Applications > Utilities. Locate the drive name from the left hand side of Disk Utility and click on it. Click on the 'Erase' tab across the top. Part 1: Formatting USB Drive on Mac Step 1: Open Disk Utility. The quickest way is search on Spotlight and click. Step 2: Under 'External' tab, highlight your flash drive. Step 3: Now click the 'Erase' button at the top. Step 4: Wait until the erasing process to complete. Step 5: This. To format a drive on a Mac, you’ll need the built-in Disk Utility application. Press Command+Space to open the Spotlight search dialog, type “Disk Utility”, and press “Enter” to launch the app. You can also open a Finder window, select “Applications” in the sidebar, and head to Utilities > Disk Utility. The /Applications/Utilities folder will open. Launch Disk Utility. Click the icon for your external hard drive in the sidebar on the left. Click the Erase tab along the top of the window. From the Volume Format menu, choose Mac OS Extended (Journaled). Enter a name for the external hard drive in the Name field. Click the Erase button.

So it’s worth a few minutes of your time to check your connection. See if the bad update was installed Follow these steps to see if the update was installed on your Mac. • Launch the System Information app ( Applications > Utilities or hold down the Option key and select Apple menu > System Information. • In the left column, look for the Software header and expand it if needed. Select Installations. • In the list in the top section of the main window, click the Software Name header to alphabetize the list. • Scroll though the list and look for “Incompatible Kernel Extension Configuration Data” in the Software Name column.

Then look at the version number. If the version is 3.28.1, you have the bad update and will need to get the latest version. Install the new update via Wi-Fi Wi-Fi still works, and you’ll use it to get the update.

No connection? Follow these steps to figure out what's keeping your Mac off the Internet. This is OS X’s way of offering to help debug your connection problem, and I suggest accepting that.

Get connected over Wi-Fi and follow these steps. • Launch Terminal ( Applications > Utilities). • Enter the following: sudo softwareupdate —background This will update Incompatible Kernel Extension Configuration Data to version 3.28.2, which will correct the problem. How to fix without an Internet connection If you can’t use Wi-Fi, the fix is more complicated. It involves booting into Recovery Mode, using Disk Utility to mount your Mac’s internal drive, running Terminal, entering a command to fix ethernet, restarting, and then using an ethernet connection to get the fixed update.