Q: OSX Yosemite Wifi issues

Having the same troubles myself. 5GHz doesn't work at all, and 2,4GHz N-only network is slow. I run Tomato on my router and if I force the "Transmission Rate" to 54Mbit atleast it goes a bit faster... If not I am stuck at around 6Mbit receiving, while uploading is a bit faster.

So if you can fine tune your router it might be an idea to lock the "Transmission Rate"...

My Macbook 2008 connects at 130/130Mbit (full speed). But if I force the "Transmission Rate" then it also goes to 54Mbit...

EDIT:

I discovered that Yosemite doesn't like "802.11n Preamble" set to Greenfield... Shouldn't be a problem usually, but looks like the drivers doesn't like it. So set it to "GF-BRCM" or "Mixed Mode". This might also fix 5GHz troubles (will test this at work where I have a 5GHz AP).

I discovered that Yosemite doesn't like "802.11n Preamble" set to Greenfield... Shouldn't be a problem usually, but looks like the drivers doesn't like it. So set it to "GF-BRCM" or "Mixed Mode". This might also fix 5GHz troubles (will test this at work where I have a 5GHz AP).

Before when I had to Greenfield I got 6/7 (TX/RX) Mbit, but now I get 144/144.

Before I figured this out I also found another "workaround" and that was to force the "Transmission Rate" to 54Mbit (better than 6), but that lead to a decrease of on my other N-devices that doesn't behave buggy.

I'm having a look into this. Not sure what I can do since my troubled iMac is connected to a bridged Airport Extreme (old). But i can set it to the different types so will go through them and map my issue across them. maybe this will help my situation. If it is an issue between my office iMac and that router it won't be so bad because the main router that the main house runs on is where all the real hard routing work goes. That would be unacceptable to slow down.

I was having the same issues on my 2014 iMac Mac with 10.10.01 and problem persisted with update to 10.10.02.  I only used the iMac offline and my pwr book  for online.

I tried all of the previous advise, nothing helped. But now I turned off Bluetooth and whoops ... my safari ran flawless!  Turned Bluetooth on  ... and all is still OK. Right now,  I'm working online for 5 hrs without any issues. thanks mattjh.

Add me to the group having major WiFi issues with the Yosemite upgrade. Went from ML to Yosemite with no other changes (Apple Airport extreme router purchased just last fall). WiFi doesn't drop out completely but often slows to such a crawl that it becomes unusable. Flash videos load slowly or not at all, webpages hang for nearly 20 seconds before they finally start to load. Using a MBP (Retina, 15-inch, Early 2013). The most frustrating aspect of this is that WiFi under ML was flawless and now...

I've tried much of what has been suggested here to no avail. Luckily I only upgraded late last week so will be going back to ML using my clone but this has been really frustrating as an Apple user since the original Macintosh was released. I guess I'll keep an eye out to see if this issue ever gets resolved.

Thank you so much!!! This has worked really well! Was extremely frustrated and this solution worked superbly. Thank you

Yes, still experiencing the same issues in an enterprise environment. Running 10.10.2 connecting to 802.1x network. Intermittent - some machines work reliably and others don't. Same configuration profile that we used for Mavericks and worked without issue.

I had terrible problems with fierst wi-fi dropping and then the wi-fi card not being recognized at all. What did the trick for me:

get an external drive and connect via USB.

Download yosemite and install on the blank drive.

Boot from the new drive - wifi is functioning.

restart and now boo ton your internal drive. Wi-fi card is now recognized and wi-fi won't drop..

No idea what it does and how it did it, but it seems to be working. 4h online now, note that my macbook pro didn't go to sleep once and hasn't been restarted since. Hope this help someone

it's annoying but with Yosemite 10.0.2 and the latest security patch 2015-03 I am having issues with my WiFi connection. WiFi is provided by an AirPort Extreme (2nd generation).

I've read a lot about WiFi problems and I've noticed that I just see the Internet globe on the AirPort Utility application started on my MacBook Pro 13" Retina (there is no status beside the AirPort) but on an iPhone both devices are showing the green "Ok" dot. But since updating my MBpro most of the time the WiFi connection is broken. This really bad. I have tried almost every suggestion provided on the Internet without success.

There are three other MacBooks running on Mavericks without any problems and more than 5 iPhones all having a reliable WiFi connection but with Yosemite nothing goes.

The only useful solution currently is to connect this Yosemite MacBook with a cable to the router.

Awesome! Thank you - this worked like a dream for me after weeks of suffering. My Mac Mini went from unaccountably crawling wifi speeds and lots of dropped connections to flawless results on a par with the other 5 Macs in the house. Thanks so much!

I've been trying various fixes again to see if (for me) 10.10.3 might be a bit different in this issue. Nothings worked. I thought that changing the bridged routers network type worked but it was short lived. I've even got a brand new cable between the main router and the bridged router. grrr. Might have to move my office back into the house.!!!

Well I've seriously had enough now, I reported this in October 2014 and now 6 months on do not have a fix.

For the record my wifi works flawlessly until I turn on Bluetooth, then it plummets from 74Mbps to anywhere between 29 and 0.02Mbps.

Non of the 8 x OS seeds have fixed my problem

I use a Magic Mouse so I can't turn off the BT. Will go rummage for my old wired one and try it.

On a disturbing note I have noticed my iPad doing the delay thing. Load a page or two and it sits on about 5-10% for some time before continuing. Sometimes it never continues. Or YouTube stops and never starts again. Toggling the Wi-Fi doesn't change this. Have to reboot the iPad mini. This has only just recently started happening.

This made my 5GHz work to (got no IP before). If your router has the ability to disable Greenfield for GF-BRCM or Mixed Mode try that... Worked for ALL the machines on work so should work for you to.

simen wrote:

 

I discovered that Yosemite doesn't like "802.11n Preamble" set to Greenfield... Shouldn't be a problem usually, but looks like the drivers doesn't like it. So set it to "GF-BRCM" or "Mixed Mode". This might also fix 5GHz troubles (will test this at work where I have a 5GHz AP).

 

Before when I had to Greenfield I got 6/7 (TX/RX) Mbit, but now I get 144/144.

 

Before I figured this out I also found another "workaround" and that was to force the "Transmission Rate" to 54Mbit (better than 6), but that lead to a decrease of on my other N-devices that doesn't behave buggy.

I'M unsure that you can do such a thing with Apple Extrems? I have two making up the primary part of the network. Some expresses on the side for speakers etc. Although I havn't activated either of them for months.