Q: OSX Yosemite Wifi issues

So I managed to do a clean reinstall of Mavericks following these instructions, and voila, my WiFi is working perfectly again.  I'd recommend others do the same until Apple sorts this out, which could take months for all we know.

UPDATE on the dual bandwidth router connectivity

I just received the usual request for password when switching from 2.4 to 5 Ghz - for test purposes.  Didn't bother filling in password cos I know I will get the invalid response (on the 2.4 it doesn't ask for the password)  Then I was distracted and on returning to switch back to 2.4 noticed I was connected - to the 5Ghz..!!!!

And for those of you who know as little as me: if you alt+click on your wifi connected icon you get more info on the connection which I think some people on this thread are quoting info from

BUT note that the article is dated July so in 1 respect I know of there is a big change: Mavericks is no longer available on the App store.

PFJ30, You should not need to adjust anything on your router. For what its worth I am using the latest Airport Extreme AP and I was having really poor performance over wifi. However, I did not adjust anything on the Airport Extreme. I just set the MTU to 1400 on the wifi card on my late-2011 macbook pro.

I have been running this way under heavy use for almost 24 hours now and everything seems OK.

PFJ30: If you upgraded to Mavericks from Mountain Lion, Mavericks will be available in the App Store under your "Purchases" tab. (If it doesn't show up, go to Store->View My Account, then click "Manage" under the Hidden Items header, and unhide Mavericks from there).

If your MacBook came with Mavericks, you might be out of luck with the downgrade, unfortunately

Clever! Thank you I did upgrade to Mavericks 

I wouldn't know how to access the card in my MBP...?

Given that I was able to change the MTU when logged into the router through ethernet connection is it possible I have changed the settings on the card but thought i was changing the router?

(Yep some of us Nil points are pretty clueless )

Thanks

Same with me. WiFi just drops and after a bit you can get it back. It won't stay up long enough to a Time Machine backup after the big Yosemite upgrade. Tried a few "fixes" on the net, but none have worked yet. Changed to wired ethernet to get a backup.
C'mon Apple ! How could this slip through QC ? And how can it take so long for a fix ? It is 100% reproducible for so many people !

Not Just clueless I was confusing where I changed the bandwidth names; I changed the MTU via systems prefs but didn't know I was therefore changing the w card  Duh

Sorry, Cubism, just back from work. yes, this is normal in Terminal: you get no feedback at all and the cursor is not moving while entering your password. You get a system answer, though.

Welcome to command line computing...

Hi Sisterlucy, only recently back from work sorry!

Open Terminal  and copy & paste:

   defaults write com.apple.NetworkBrowser DisableAirDrop -bool YES 

restart your computer.

Thanks Rick

But I'm on those settings already. Have tried resetting the modem etc, and no joy.

rickfromadelaide wrote:

 

I found the wifi issues stem from wireless router settings used with Mavericks and previous OSes.

Yosemite appears to want more secure settings.

Change the wireless security settings on your router to those shown below:

Network Authentication to WAP2 -PSK and Encryption to TKIP+AES.

 

These settings produce rock solid wireless with Yosemite but give Mavericks the very same wifi problems.

Am I right in thinking that if I was to factory reset my MacBook Air on Yosemite it would automatically restart on Mavericks as that's the OS it came with? (As in I don't need to create a bootdrive for Mavericks)

Can anyone confirm this is true?

Is the system answer blank? I just get a blank new line.

hexdiy wrote:

 

Sorry, Cubism, just back from work. yes, this is normal in Terminal: you get no feedback at all and the cursor is not moving while entering your password. You get a system answer, though.

Welcome to command line computing...

Well, for some strange unknown reason, I have had no trouble since last night after I got on the Forums.............I just knew it was my Internet Provider!!!