Q: Wifi is incredibly slow on OS X El Capitan

Sadly yesterday's 10.11.3 didn't resolve the Blue-tooth > wifi issue.

I have 2 Apple Bluetooth mice, both effected the same.

An impossibly slow Bluetooth>WiFi connection seems to be a very well known El Capitan problem with lots of people complaining to Apple and lots of comments on websites - and of course suggestions but none of them seem to work for those affected. Why everyone isn't affected remains a mystery.

Lots of us hoped/prayed yesterday's 10.11.3 would fix this bug - but no.

It means that off-line I can use my Apple Blue-tooth mouse/mice but have to switch them off and revert to a clonky wired mouse for the Internet - the same with my Apple Blue-tooth keyboard. It's an absolute pain in the *ss.

I just "upgraded" to Capitan and my internet connection is ruined, every minute my internet connection stops for a minute, and starts streaming again a minute later.   I did all the shut down and reboot stuff with the wifi and computer and it hasn't helped. 

This is a serious waste of my time to research and try to fix this.  I HATE you Apple.

same issue here - wifi so slow, tried all he solutions and still awful... Apple really need to resolve this...

So I had a similar problem ... fast ethernet, fast on my phone/tablet, but slow on my El Capitan 2011 Macbook Air over wifi. I fixed it by turning off my router's 5Ghz network and just used the 2.4Ghz one for everything. As soon as I did that, boom, my Macbook was connecting properly at 30Mbps (instead of about 5Mbps). Same approach might help you.

You could try switching off the 2.4Ghz network and keeping the 5Ghz one, but I have some 2.4Ghz devices only that I need to support. Plus I want the superior range of 2.4Ghz.

did u find any solution ?

Not yet, but then I haven't yet worked out how to try switching between 2.4 Ghz and 5Ghz on our [excellent] French Livebox router - assuming that is possible.

But this is a new - and I assume El Capitan - issue. Before El Capitan it was all absolutely fine. Since El Capitan there is a new, serious and infuriating Blue-tooth/Wi-Fi connectivity issue STILL not solved by the 10.11.3 El Capitan update

CN

PS I say our excellent French Livebox router - the whole of the French phone system is now basically internet-based through the LIvebox and works absolutely faultlessly as does our associated TV etc.  So I hesitate to start fiddling with it - and we have windows PCs etc attached to it too. All I want is for my lap-top>Livebox WiFi connection to go back to working properly [or at all] - as it used to pre-El Capitan.

SUCCESS!

Like w1nt3rmut3 above, I found out how [pretty easy] to set up my French Livebox to run only on the 5Ghx network for my Macbook - and I've 100% lost the interference from Bluetooth for my Apple mouse - hooray!

That said, this was never any issue before El Capitan.

If you haven't resolved this yet, maeliz5412, I'd try the 5 Ghz v 2.4 Ghx router settings idea. 

It worked for me - and I was going NUTS.

Good luck.

So it's interesting that you mention this. I get constant beachballing since upgrading to El Capitan. When I have GMAIL and Yahoo Mail open, Yahoo Mail actually tells you that there is no internet connection and suggest you go to system pref and use the diagnosis feature. By the time I do this the connection is re-established. I did just try having this computer use only 2.4ghz and the beachballing initially seemed to go away quicker. No other app actually tells you that the Internet connection has dropped. Finally at the bottom of gmail it says waiting for cache. At the bottom of Yahoo it says waiting for comet. Anyway, I'm so tired of trying to troubleshoot this.............................................

sdf007, my problem may be different in that it was my Bluetooth [so my Apple wireless mouse] that was interfering with my laptop>to>router connection. What solved this problem for me was disabling the 2.4 Ghz network and only having the 5Ghz network. @ 5Ghx the range is meant to be smaller but it seems fine for me at home.

It remains ridiculous that Apple STILL haven't resolved this widespread problem on El Capitan - and it was never ever like this before El Capitan and it seems to be driving lots of people mad.

charliebn its interesting that you mention this, I have a bluetooth enabled mouse. My Macbook air sits 12 inches from the router, and I rarely use it anywhere else in my house, so there is no need for 2.4. I just changed it to 5ghz only. If that doesn't work I may try an old wired mouse or trackball. I had no problems on yosemite.............

Hi sdf007. When my very-slow-hoplesss wifi problem first started [with El Capitan - NEVER before] I read somewhere about Bluetooth possibly interfering with the 2.4Ghz connection. I found that if I switched off Bluetooth my speed worked fine - as it always used to.  If I used a wired [no Bluetooth] mouse it was fine.

So I disabled the 2.4Ghz circuit on my [French Livebox] Router], so keeping only 5Ghz. It 100% solved my problem.

But why don't Apple TELL everyone this - it's an absolute pain in the *ss!!

Hi charliebn so I turned off bluetooth and have my computer using 2.4ghz, I left the 5ghz channel open because other devices in the house use that with no problem. I have my elegant apple wireless mouse turned off and my old wired logitech trackball hooked up with 8 tabs plus a youtube video running with no beachball, I will be so ****** off, not at you, but Apple if this solves the problem................I'll let you in a day or two.

If you find that does work, sdf007, why don't you just switch off your 2.4Ghz circuit - or do you have other devices that need that? I don't think your Macbook Air needs 2.4Ghz does it?

That's what I did on my Retina Macbook. My Bluetooth Apple mouse still works fine with the 2.4Ghz switched off.

So far I haven't found a single hitch doing that.

Back to beach balling, I played with various configs of wifi using the wired mouse with bluetooth off. I believe that this is some kind of airport issue as i see errors about beacon lost, etc. Also, I downloaded the newest version of etrecheck this weekend after a prompt from the version I had and it crashes and will not finish.