OSX Yosemite Wifi issues

I have problem too. I can't connect to 5ghz wifi network after upgrade to OS X Yosemite.

I tried restart time capsule, restart MacBook Pro 15" (mid 2012), remove wifi network from preferred networks - nothing changes :-/

I'm facing the same issue for my now 2 weeks old 2017 MBP 15".

Seconds after connecting to the 5ghz network, mcs index would drop to zero and tx rate drops to 7 MBPs..

The first few seconds upon connection, i would see tx rate of 878 to 1053 MBPs.. tested on safe mode and recovery mode.. same issue happens.. really vexing.. I'm hoping my 1-1 replacement wouldn't havent this issue

Just to let you know that the original issue was a software problem with an Apple wifi driver. It took 2+ years to fix and it was really frustrating.

I had a perfect high speed connection to my router (Tx rate was quite high) but packets were being dropped massively.

What you are experiencing sounds different. If your TxRate is low you need to figure out why. It's either due to interference or ... bad hardware ... or distance from router?

I have a great App that I bought while trying to figure out what was wrong with the wifi back when Apple hadn't sorted out this problem. Among other things, it shows me how lucky I am that hardly anybody in my London neighborhood is using their 5Ghz networks. I am the bright yellow one on the right and look at the mess in the 2.4 Ghz range (on the left).

Not sure if there's a free app (WifiExplorer is what I am using, from the App Store I believe):

My new Mac is by far the worst Mac I have ever owned, extremely buggy, slow updates either don't help or create new ones. Took it back to Apple with a fresh install by them and had the same issues in the store. Mine was a custom order so they are sending me another one. Hoping that ones is better. (Still under extended warranty)

You are entitled to 90 day telephone support from Apple. Try contacting them.

Apple Support Contact

Apple Support by e-mail or chat

The same has happened to me. Never had a problem with Maverick. Making it impossible to do anything more than about 2-3 minutes before wifi is dropped.

I have the same problem, pages take an eternity to open using WIFI, I can have lunch before one single page open!! frustrating!! any ideas of how to fix the issue? Have anybody tried to uninstall safari and reinstall it???

I just tried something, which so far seems to be working. Go in to your Keychain access - System. Find your wireless network - double click. There are two tabs, Attributes & Access Control. Go into the Access Control and check "allow all applications to access this item". Mine was defaulted on confirm before allowing access, which I think was knocking me off every time I tried to do anything.

I'm not sure, but this is the first 10 minute period I haven't been knocked off since upgrading last night. Good luck!

I will give this a shot and keep my fingers crossed 😀

I have the same issue with WiFi. WiFi drops every 3-5 minutes. It does not depend on router. I have the same issue at home with Airport, at work with Cisco and at my mother home with Netgear. I had no problems with Maverics.

I have Wifi issues too. Under Mavericks everything was fine. After doing a clean install of Yosemite I have a terribly slow connection on 2.4 Ghz. On 5 Ghz everything seems to be OK. Very strange.

Macbook Pro Retina Mid 2012

Turning off Bluetooth solved my problems on 2.4 Ghz. There seems to be an interference between Bluetooth an Wifi.

This is SOO annoying. Mavericks had its issues with JUMBO Frames that was never fixed but this is crazy now. Last night I upgraded to Yosemite from Mavericks. Now I can see my 5Ghz SSID but only have internet for 30 seconds at best. I don't even see my 2.4GHz network at all. If I toggle Wifi on and off I see the 2.4 for a moment and then gone. I removed all favorite wifi's and manually configured the 2.4 and will not connect. Removed that one and tried 5Ghz and same 30 seconds. I have done all updates, I have restarted numerous times and no go!

I did a fresh (clean) install. I formatted the HDD and had the original Lion install by default that came with the unit. It booted, had internet fine and then upgraded straight to Yosemite and immediately no wifi. Can anyone say if they did a clean install but from Mavericks and upgraded to Yosemite with same results??

What kills me is that apple doesn't seem to be giving ANY information out, no acknowledgement, and certainly no fix yet. I feel more and more like I am purchasing Microsoft Products where I am beta testing. If apple knew in Beta releases this was an issue with ALOT of people, they should not have released this yet! My laptop is my business and I am now tethered to a cable for everything!

Bluetooth disabled made no difference for me. Also I found that if I disable wifi while using my ethernet it will disconnect connectivity from ethernet until I unplug and replug...

APPLE ??? I guess I should just make some apple juice? or can I get some lemons??

I installed Yosemite on two computers: a 2013 Macbook Air and a late 2013 Macbook Pro. No problem with the latter one. Unresponsive Internet via wifi on the Air using my son's account. What is strange is that the Internet speeds are fine on the same Air using my own account with Administrator privileges. I tried some of the suggestions above as well as removing parental controls on my son's account, but no luck so far.