Yosemite: No internet for 5GHz wifi

Please report errors of this nature to Apple, as development does not read these forums

I would encourage you to file a bug or feature enhancement with Apple at either:

BugReporter

<http://bugreporter.apple.com>

Free ADC (Apple Developer Connection) account needed for BugReporter.

Anyone can get a free account at:

https://developer.apple.com/register/index.action

And/Or

Mac OS X Feedback

<http://www.apple.com/feedback/macosx.html>

IPod Touch Feedback

<http://www.apple.com/feedback/ipodtouch.html>

The more people that report a problem, the more likely it will receive a higher priority. Plus each report will have a different perspective that can help the developer identify the root cause.

I've been having the same issue, but the odd thing is that it only applies to Apple-based internet using programs (safari, feedback assistant, iTunes, App Store, etc.) I'm using Mozilla Firefox at the moment to write this reply, but anything else seems to not accept a network connection for some reason, even the diagnostic system on the computer says that there's a solid internet connection.... quite the strange occurrence if you ask me.

Same issue here. Internet work for none-apple based internet program. Also, softwares that install icons on the menu bars, such as dropbox or evernote, are not connected. I am using Chrome to type right now.

I've also found this to be the case. I began having problems on Friday, shortly after I installed Yosemite. I found a suggestion (allegedly made by an Apple Tech. Support engineer) to blow away the .plist files in /Library/Preferences/SystemConfiguration. I did that, and my box functioned fine until Sunday evening, when my WiFi dropping problems reoccured. I tried deleting the .plist files again, to no avail. I finally disabled the 5ghz WiFi connection to my Airport Extreme, and all has been well since.

Using MBP 13 Retina (Late 2012) with ASUS RT-AC66R Dual Band. After upgrade to Yosemite I cannot connect to the 5GHz at all, 2.4GHz worked fine for some minutes and then dropped to ridiculous slow speed until final break off. Not a router issue as all other devices in my home continue to work fine.

After trying everything else I disabled Bluetooth and could re-establish a connection on 2.4 band (5 still not working). Turning it back on creates same issues as before. Nasty bug and I hope for a quick fix from Apple.

I can't say whether this will make any difference, but you could try setting the router to channel 48 only rather than letting it choose its own channels. Some channels, specifically most above 52, require a special protocol which for example some Android tablets don't have, so they will connect at channel 48 but not above. AFAIK Macs haven't had this problem in the past, so very likely this isn't the issue here, but it can do no harm to try. It would seem unlikely that Apple would actually remove a wifi protocol, but then considering other facilities which have disappeared nothing would surprise me.

I went through some more testing with my configuration. Finally, I've reactivated my old Apple Airport Express Basis, cabled it to the ASUS router to keep my IP range for NAS etc. - this did the trick for me. I could switch Bluetooth on back again, my WLAN stays well around the 200 Mbps and stable. I had not a single drop off after this again from my MBP. For me this smells like an incompatibility with some routers, especially dual bands.

I'll keep this config running now until Mac issues an update and enjoy Yosemite, which I think is still a great OS.

i've been playing around with the 5GHz wireless settings and found this temporary resolution, I hope it will do the same for you. I set the Channel Bandwidth of my 5GHz Frequency from the default 20/40MHz to just 20MHz, apparently 40 and 80 got some issues. Downside is, my speed slowed down to about half but still slightly faster than the 2.4Ghz.

If you're not getting Internet when connected via 5 GHz, it sounds like your router isn't properly sending your DHCP information.

Try rebooting your Wi-Fi router.

This is Yosemite bug. Can not use switch on wifi too on Macbook air 2012. Apple, aplle, what you are doing ? :-)

I have tried all solutions, even boot recovery partiion and not working .....

Exact same problem here, since the Yosemite upgrade on a late 2013 iMac.

Wifi will work OK with 2.4, but sluggish at best with 5GHz.

Done.