Apple’s OS X blacklist accidentally disables Ethernet in El Capitan

“If you’re having problems with your Mac’s Ethernet port this morning, the culprit may be an errant automatic update that Apple published over the weekend,” Andrew Cunningham reports for Ars Technica.

“If you’re reading this and your Ethernet port is working fine, odds are good that you’ve already installed the follow-up update released to fix the problem,” Cunningham reports. “The culprit is an update for System Integrity Protection, the El Capitan feature that protects some system folders and keeps unsigned or incorrectly signed kernel extensions (or ‘kexts,’ roughly analogous to drivers in a Windows or Linux machine) from loading. ”

Cunningham reports, “In this case, the kext used to enable the Ethernet port on Macs was blacklisted—if you restarted your Mac after applying this update but before your computer had a chance to download the quickly issued fix, you’ll find yourself without an Ethernet connection.”

Read more in the full article here.

MacDailyNews Note: Instructions for the fix is here.


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      1. I use private browsing, don’t allow cookies, and start a new browsing session at least twice a day. (Yes..I sign in every time I want to comment here..).

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  2. Over the weekend I walked through this problem of no ethernet connection with an Apple repair tech. He had no idea about this update that Apple pushed, neither did I. I had an appointment scheduled for Wednesday to take my 27 inch iMac in to the Apple Store because Apple care told me that the ethernet was toast on my computer and I was going to get a new one. Thanks MDN, you fixed my computer 🙂

    Maybe the Apple Care Representatives should read Mac daily news a little more?

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