Hi I turned my computer on this morning and the Ethernet port has decided to stop working for no reason. it doesn't even know there's a cable in and I've tested the cable on my other computer and that works fine. Do you think the port is actually broke? (I can't use wireless as it's not fast enough for my purpose). Thanks
iMac (21.5-inch Mid 2011), OS X Yosemite (10.10)
Try resetting the SMC Reset the System Management Controller (SMC) on your Mac - Apple Support
Try another cable anayway and make sure the cable is tight in the port.
I had the same problem. It seems to be a silent security update gone wrong. Read more about it on Reddit:
https://www.reddit.com/r/apple/comments/47tfos/warning_software_update_03151913_ breaks_ethernet/
I just downloaded and installed OS X again and it solved the problem. Maybe not the fastest solution but a very easy one.
I've tried that but thanks for your answer.
Alright thanks I'll try that
Same here. Worked last night, this morning it was dead. Changed cable; same thing. Works on wireless but I'd rather use the ethernet connection. I wonder what happend. I tried resetting everthing to no avail. In network settings it says there's no ethernet connection.
Hi everyone,
I have an iMac 21.5" 2012, I installed OS X Version 10.11.3 (15D21) it two days ago and this morning, as you all, I have the message following error appears when i want to activate my card via the Ethernet terminal "ifconfig: en0 interface does not exist" when my Mac is directly connected to the router.
In this network parameters also displays "Ethernet Not Connected" ...
Do you think Apple will make an update to fix this problem or I would have to reinstall OS X? IF I reinstall OS X, is this going to delete my programs and files? What do I lose by installing OS X?
Thanks,
Alexandre
I expect that Apple will release a fix.
I too have an iMac which suddenly says that the Network Cable is not connected this morning. Rebooting does not resolve the issue. I booted up into recovery mode, and the network interface seems to be working there, but when booted into normal mode, it stops, and acts as if there isn't even a working piece of hardware to connect to. Very confusing.
I just restarted my computer holding down the command+R, chose re-install OS. Did it wirelessly. Fixed issue. Not too quick of a fix but it worked and all my files are still intact. Apple apparently broke this with a silent update. There will probably be a fix rolled out if you have the patience to wait for it.
It's not random, LOL. It is bad code - security patch that really helped you out by knocking you offline for the weekend.
My ethernet port died yesterday after a restart. I contacted Apple Support. They had no clue what was going on, and told me to take it in for a repair.
https://discussions.apple.com/thread/3880714
This helped me on yesterday.
Ethernet randomly stopped working on my iMac
