Yosemite (OS X 10.10) killed my WiFi :(

Deleting everything in Library/Preferences/SystemConfiguration and rebooting fixed it for me. My wifi would shut down after about 30 seconds. Now it actually stays up at least for a few hours anyhow. None of the other suggestions worked for me.

Great point. In my experience (MBP Retina 15" Later 2014), I have only experienced drops with WPA/WPA2-Enterprise connections. The WPA2 Personal connection are stable (I tried both on 2.4 GHZ and 5 GHZ).

Original post:

JFMezei

Just a quick comment:

It would really help if people who post about problems with Wi-Fi described the wi-fi system they are connected to. (WEP, WPA2 Personal, Enterprise (and what subprotocol such as LEAP EAP-TLS etc - Pressing ALT when clicking on the wi-fi icon on menu fbar gives you details of how your computer connects to the wi-fi network.

If a trend comes out with problems happening only on certain types of connections, then it would help make formal bug reports to that now alien company in a spaceship landed in Cupertino.

GalagBasha: the recommendation from you worked for me too. Fantastic - connection problem solved. Back up to 35 MBPs from a connection that was not functional.

The good folks at the Apple Helpline gave me this solutions and it worked.

Open Finder > Choose Go From the menu at the top of the screen > Click on Computer > Double Click on Macintosh HD > Double Click on Library > Double Click on Preferences > Click once on the file called "SystemConfirguration" > CMD+DEL the file > Enter your password > restart.

+1

Same problem here with D-Link DI524 2.4Ghz. I've tried everything posted on this post but still with the issue. If I turn on BT on my MBAir the wifi signal is killed. With Mavericks no problem, certified.

:S

One thing some people haven't looked at is their Preferences in their Home User Library. Since Apple made this folder invisible awhile back to keep folks from changing things and screwing everything up, some people have just forgotten about it. Me included. So I did the ~/Library and this is what I found in my Home Prefs Folder.

These plists tell the system to use them rather than the default system prefs. If you have duplicates plists (enlarge image)

they more than likely have different prefs set up. If so, they cause conflicts in the system and the app or program will

not function properly, usually leading to a crash or a freeze. In my case, I dumped the entire Home prefs

folder, did a shut down, then restart. I shut down again, and did a PRAM reset when I restarted again.

Everything I have run since then has worked properly, and has all day. You do have to reset your prefs for the plists

you delete, most certainly your network prefs. It may have been a bit of overkill, but I could not sort out which

plist was correct and which was corrupt. This exercise tells me my Yosemite System Library is fine, but my Home

User library did not copy correctly when I downloaded Yosemite.

Installing Yosemite was the biggest mistake I have EVER made. downloading Mavericks right now from my workplace to revert to it tonight. never thought that Apple could ruin my iMac.

Believe it or not, adding an Exchange Internet Account also killed my wifi. Cant use it with Mail.

Just spend hours taling to Apple support theY just talked me through removing Yosemit. Reinstalling maverinks right now. Can't deal with this right now. Just spent a but load of money moving from windows to Mac 5 days ago. forked out the extra because I thought I would escape this sort of thing. I thought that's what Apple was all about.

My question would be how are we to download a fix if we can't be online for more then a few minutes.

Same problem here;

Updated the OS (Yosemite) and a day later I have no WiFi connection. WiFi works fine, but not with Yosemite! Now I'm wired until who knows when!?!

Any word re patch/update?

MBP, 15", Late 2011

It worked for me at least for now. Though I need to search my wifi name in all key chains.

So guys, Apple just contacted me and said that this would work:

Turn off your wifi, go to finder and press COMMAND - SHIFT - G, and then type /Library/Preferences/SystemConfiguration (Caps are important according to the advisor) and then press enter.

Inside the window, look for NetworkInterfaces.plist. (Delete), and then Preferences.plist. (also delete).

Go to the apple icon on the bar and reset your mac.

You should have wifi after restarting.

I did it and i have wifi now. Some users are claiming that this does not work and it has to be a matter of luck, i'm just glad my computer is working again.

Hope it works! Good luck!

But doing this blows away all your past learned access points, so you need to re-enter passphrases when you need to reconnect to them again, right? That's a major drag for some of us... but then again so is quasi-loosing network several times an hour.

-r

Have just the same issues and symptoms as you after upgrading to Yosemite.

My device is MBPr 15" Late 2013 (bought early 2014).

So weird! Just two weeks ago colleagues from IT infrastructure upgraded our corporate Wi-Fi which covers several automotive dealerships in Moscow and SPb to WPA2-Enterprise (with EAP and user-certificates and all this). After that it worked fine for me for about a week (while MB was still on Mavericks), but then I installed Yosemite. That was a mistake of mine! Now have to pay for being hasty. :-)

At the same time at home I have UniFI AP with WPA2-Personal security and it works without any problems. Specially tested wi-fi stability at home for the last 3 days. Cause usually at home I prefer to use Ethernet-TB adapter when seating at my desk. This increases transfer speed between MacBook and my Synology NAS from only 5-7 MBytes/s (~40-70 Mb/s) to awesome 70 MB/s (600 Mb/s, which is pretty close to maximum which NAS can provide). But even with those not so high wireless speeds I'm pretty happy with Wi-Fi at home - low performance is easily explained: we have dozen of neighbor' wireless networks here, my own access point has to cope with 10+ family devices at a time and it is only 802.11n standard (not ac). So no problem here.

But working in the office is now one big problem for me. Pity, we don't have wired connections in the offices for notebook users. :-(

Hope Wi-Fi issues are going to be sorted out ASAP.

JamieAscot's solution Oct 18, 2014 3:31 PM worked for me 🙂

MacBook Pro (Retina, 13-inch, Late 2013)