Q: Wifi disconnects after sleep and takes long time to reconnect with Mavericks

Also working great for me on Yosemite, with non-apple router.

Thanks for sharing!  As mad as I want to be at Apple over this, its also possible that substandard equipment could be causing it.  Is there anyone out there that has this issue and also has Apple Wifi equipment?  I'd be very interested to know

I have had this problem with several Mac Laptops, and it recently started to happen on my MBP which just came back from Applecare with Yosemite installed.  After reading this thread I realized that I solved this problem once before by deleting all the preferred networks in the network system preferences and also by removing any entries in the "Search Domains" under the "DNS" tab.

I hope this helps.

I tried turning off my Apple TVs but it didn't fix my problem

Strange enough, this wifi problem started to happen after I bought my new Apple TV 3rd gen, or after the Yosemite update with the Photos app.

On my MBA 13 late 2014.

My MB white, late 2009, same OS version, has no issues -.-

I isolated my issue to Safari only. Other apps and browsers were connecting ok.

I could only fix this issue by performing a clean install of Yosemite.

The thing that finally fixed it for me was from this here on Apple support:

OS X Mavericks: Choose preferred Wi-Fi networks

I found that in preferred networks i had an old optus mobile network which i used before getting fixed broadband when i moved into my apartment, and also my iphone's network. After deleting them from preferred networks and keeping just my current router's retwork, all seems to be working fine on my macbook pro. I've tried both putting it to sleep by closing the top, and also leaving it 15 minutes to go to sleep. In both cases I had an instantaneous connection.

Hope it works for some of you.

I should add to the above post that I didn't need Step 2, and also I didn't need to create a preferred network as there were already three that had somehow been saved. Presumably the problem is that the computer keeps scanning for the other networks too before settling on the one I normally connect to.

Yes, we have all Apple routers, and had the same minute delay connecting to WiFi. We fixed it by repairing the hard disk with Disk Utility. I'll post full detail at the bottom.

This fixed it for me: we used Disk Utility to Repair Disk.

That was it. We had the same exact problem, namely that when we woke the MacBook Pro (with Flash Storage, Retina) it would take up to a minute to connect to Wi-Fi.

It turned out that the startup disk was slightly corrupt, and for some bizarre reason, repairing the disk was all it took! You should try it; after all, it can't hurt. We did the fix more than 10 days ago, and haven't seen a recurrence of the problem even once since then.

I believe the cause of this issue is not just a single one, and it may depends upon several (unkown) factors.

In my case, after months of troubleshooting, I have definitely fixed this way: my home LAN is made up of a central router and a wifi-extender (both Netgear). I noticed that the slow reconnecting issue was not happening when my MBA was in the main router range, but only with the extender. Suspecting in a DHCP  issue, I have set up my Mac into the "reserved address" list of my main router, assigning it an IP. In this way, there is no DHCP handshaking during the connection and.. voila.. the issue disappeared forever. Now I am connected as soon as I lift up my lid.

Fabio

For me, turning on Power Nap solved the issue.

Switch off wifi than back on and it connect automatically. no need for power cord

Have to switch off wifi and than back on and it connects automatically for me

Separating 2.4GHz and 5GHz wireless bands and giving them different SSID names solved my problem permanently. Thanks!!

I have a Macbook Pro 15 Retina with OS X El Capitan and a non-Apple router supporting dual-bands.

Moving regularly used network(s) to the top of the list worked for me too.

I had replaced my BT router - the new one therefor appeared about towards the end of my ridiculously long list of networks.Presumably the whole table to that entry was being searched everytime. I had got 'remember networks' ticked - so MBA was doing precisely what I had asked it to do.

Because I use keychain every single network access from every single Apple device was on that list.

I removed a lot of the redundant ones at the same time.

Having read many posts on this thread though it does look as if there are several problem conflated under this heading though  - inevitable I guess with this kind of problem.

  Maybe try a few proposed solutions yourself, rather than wait for a fix from Apple for a soution which may be down to your own particular config?

Good luck.