Q: wifi keeps dropping since Yosemite upgrade

Same problem. Tried everything suggested. None helped. Did not happen with Mavericks on the same machine.

2013 Macbook Air

Hi that is correct there is to many complaints to be singular,i have had the beta for months and have made 25 feedbacks to the feedback assistant about no wifi and wifi dropouts but to no avail,i don’t know why they do it if they will not listen or act,but the way i have been getting by is to on the top right of my iMac turning off wifi and then turning back on and that fixes it until the next time

I'm not just getting the constant wifi dropouts, which seem to be worse on a 2.4GHz rather than 5GHz connection.

I'm also getting incredibly slow transfer rates over WiFi - cannot get above 5MB/s on Wireless ac connected with just me on it, and no interference.

Works 100% speedy and stable with Mavericks - so this is a Yosemite issue, and they have been told about it on several occasions.

Guess there were more important bugs to fix before release day.

My view, they should have waited a few more days to fix these and release on Monday or a week later - like they are with iOS 8.1

Same issue. Wifi works, but dropped down to 0.5 mbps like in f***ing old dial-up ages. I tried to turnoff BT, delete SystemConfiguration, no results.

iPhone works fine, Windows works fine, even my dog can connect to the internet except 'Most Advanced Operating System'.

Sad.

Yep - same problem. And I ran through 3 Yosemite betas without this happening, then the "production release" and boom!  I can't correlate it to anything special, just about every 10-15 minutes Wi-Fi goes dead.  A reboot brings it back up. I've turned Bluetooth off we'll see if that helps. (MacBook Pro (Retina, Mid 2012))

Ok, this is worked for me:

1) Go to Computer > Macintosh HD > Library > Preferences

2) And delete WHOLE folder named 'SystemConfiguration' (if it asks you for your password, enter it)

3) Restart

Works for me like a charm. Hope this helps 4 you.

PS And yep, this problem appeared only in final release - I has not this problem with all betas.

Quick follow-up (then I'll try the "delete the SystemConfiguration" route) - I ran diagnostics, and wi-fi came back (without a reboot).

I too have this problem and I checked and I also have the same specs as you do.

Card Type: AirPort Extreme (0x14E4, 0xEF)

Firmware Version: Broadcom BCM43xx 1.0 (7.15.124.12.8)

Not sure if that means anything.

I reported earlier about BT and WiFi dropping as soon as I turn on the BT.

This helped, hopefully for good, I rebooted the Time Machine, Airport Extreme and the provider router, and the MBr (late 2012).  It has been almost 24 hours and I have not experienced the dropped wireless and BT.  I hope that stays because this is my work setup..

I turned off BT, removed location, removed network, removed system prefs folder, re-added after reboot, and still the wifi drops in Yosemite OS.

I have a theory. See what you think.

The Yosemite wireless function gets screwed up when switching between 802.11g/n and 802.11ac radios. Normally this switching between radios, based on signal strength etc,  isn't an issue, but for whatever reason Yosemite can't handle this behavior and loses connection completely during the scan/swap.

As a test, I separated 802.11g/n and 802.11ac traffic into two separate wireless networks. Then connected my 2013 Macbook Air and 2013 Macbook Pro Retina to the 802.11ac one (selected from pulldown). So far so good. Obviously, this isn't ideal, but it might be much less annoying than dealing with constantly dropped WIFI in the short term until Apple releases a fix. I should mention that the problem was consistent on both laptops, even when not roaming between base stations.

I've seen similar problems with Mavericks on the newer 802.11ac Airport Extreme products when I used to use them.

My wireless equipment are Ubnt UniFi AP-AC units running 3.2.5 firmware.

I'll continue to monitor and update this thread if anything changes. If anyone could test the theory I'd appreciate it.

Rob

I originally thought the same when I had the issue in DP5, but at the time I didn't have wireless AC and only N.

I now use a Cisco 3702i so can try loads of customization options, nothing worked and I was only able to get about 4MB/sec maximum performance.

Even when sitting 1m away from the router.

But using an identical laptop with Mavericks right next to it, I see the kind of performance you would expect from a wireless n and wireless ac connection.

EDIT.

It's only effecting wireless, I've just got a thunderbolt to gigabit ethernet, and that's fast.

Same here.  Disabling/Reenabling wifi each time as a temporary workaround.

Add me to the list of affected people.

Mid 2012 Macbook Pro Retina. Not a single wifi issue before Yosemite, now regular complete "blackouts" of connectivity that can only be resolved by dis- and enabling the wifi.

I have the same machine.  And an 802.11n Time Capsule / Airport.  I would list the exact model number, but the device isn't showing up in Airport Utility at the moment.  Maybe related.