Same here with some devices connecting and others 'connecting' but unable to do anything, most strange is....
iPhone 4 (IOS 5.0.1} connects, gets a IP address and DNS details, but nothing works (email, dilbert, Safari etc) apps either hung or state must be connected to network....
Meanwhile iPad (original version) works fine, as does my macbook (OS X 10.6.8), and sony vaio (Windows 7 x64)...
Running on 1*Airport extreme fastethernet (1st Gen.) and 1*Airport Extreme Gigabit (2nd Gen.), both now reverted to 7.5.2....
I have an iMac G5 running Leopard networked via an airport card to an airport extreme base station along with 3 iPhones of varying generations and an intel Mac. All except the G5 worked perfectly on the network after upgrading to 7.6. Ever since the upgrade the G5 will. it connect to the network no matter what I tried, including re-installing 7.5.2 and re-upgrading. The router refuses to acknowledge the. etwirk password from the G5, which worked flawlessly until I upgraded.
Woukd really appreciate some help on this. Ran network diagnostics and tried toreconfigure the netwirk setting and nothing has worked. Triedshutting the airport off and then back on. Restarting. Nothing.
This is my teen's computer and it is frustrating.
Not to deny anyone else's experience, but I upgraded both my Airport Extreme and Airport Express with no problems. Our MacBook Air (Lion), iPhone 4, iPhone 3, oldish Mac Mini (Snow Leopard) and iPad all work just fine with both following the upgrade. Sorry I can't be helpful for those with problems. I upgraded from the "Manual Setup" tab by clicking on the appropriate button.
As I said, my ONLY connectivity problem is with the iMac G5 running leopard. It is almost certainly a compatability problem with the new firmware and the old OS. This is bush leage, from Apple, frankly.
What is especially frustrating, however, is that it still won't work even after I downgraded the firmware to 7.5.2.
I found a version of 7.5.2 for my Extreme here:
(look in ~/Library/Application Support/Apple/AirPort/Firmware/version.xml for other version/products)
Was prompted to upgrade my main Time Capsule to 7.6 which reported success. However Airport Utility no longer shows my second Time Capsule (which is used as a range extender) so no way to upgrade that.
My iPhone and macbook air will no longer connect to the network - haven't tested other machines yet.
Will try the backgrading to previous firmware - apparently 7.6 doesn't even fix the iCloud/back to my mac issue anyway.
What happened to Apple's mantra 'it just works'? They really are useless these days. Very disappointed.
returned TC No.1 to firmware 7.5.2 and it's back to normal. iPhone etc. connected straight away and TC No.2 reappeared in aiport utility.
Advice: Don't touch firmware 7.6 - it's not ready and should never have been put out.
The strangest thing: it suddenly works again like Mike Edwards wrote.
I left the network for a day or so on 5 GHz only, then changed it back to 2,4 GHz and: it works.
No more authentications errors, no more No Acks in the console. Did something somewhere flush? No idea. But patience did the trick.
You have to click on the actual literal 'Version' not the number 7.5.2 or 7.6.
See attached screen shot. The 'Upload Version' is a drop down list from which you can choose 7.5.2.
I have 3 Gen 4 Airport Extremes connected via CAT5 to provide 100% wireless coverage in my house. My initial upgrade to 7.6 was a disaster. Everything broke. No access to the internet, no Sonos, and the routers were constantly dropping and reconnecting with each other and everything else. So I went back to 7.5.2. All was right again. PHEW! Then I saw that some had found success by upgrading, downgrading and upgrading again. So what the heck, let's give it another try. While the upgrades themselves were successful, I again saw the routers dropping / re-establishing connections (especially bad with iPhones and iPads). Now I'm back on 7.5.2 until Apple issues another release. Hopefully they will do a better job testing the next release after this disaster.
I use Windows 7 with Time Capsule (TC). I use my TC as a Network Attached Storage (NAS) Updating to Firmware Version 7.6 broke my network connections too. Rebooting my computer and TC momentarily solved my problems then I uploaded 7.5.2 back to my TC. My TC especially would freeze if I tried to copy any file on it. I also experienced a negative impact on file copy speeds. I've never been able to reach the promised speeds of 8-9 MB/s over wireless but I was happy with 6 MB/s over wireless and 25 MB/s over wire. However with 7.6 I could only reach up to 3.5 MB/s over wireless and 14 MB/s over wire. Wireless - 6 MB/s to 3.5 MB/s Wire - 25 MB/s to 14 MB/s I hope they find a quick solution to this problem.
I had the same problem due to updating to 7.6 (what a piece of Cr@p).
After calling Comcast repeatedly and them telling me to do this and that (which only helped for a short while before my internet connection went back on the fritz), I decided this my be a firmware problem. Sure enough .... it was.
If you have Airport base Station Express, here is what I did t o resolve the problem: (1) launch Airport Utility (2) look at top menu and navigate to "Base Station: Upload Firmware" (3) Choose 7.5.2 frok dropdown menu (4) the "update" (actually a "backgrade") installs and you are back to a painless existence.
I have a Time Capsule (3rd Gen) and Airport Express 802.11n. The Capsule is hardwired to the router (of course) while the Express extends the network wirelessly from the Capsule.
When I tried to upgrade the Express to 7.6 from 7.5.2 via Airport Utility (AU) 5.5.3, everything looked like it worked excpt AU was never able to find any of the devices after the green light reapeared on the Express.
Rescanning came up with no devices.Relaunching AU didn't help. I even launched AU from an old iMac and it's AU couldn't see find anything either. However, both computers could get to the internet.
I decided to check this board for issues - looks like there are some and then not upgrade the Time Capsule just yet. Instead, I walked away from the computer and contemplated life, the universe and wireless devices.
Returning about 10 minutes later I was surprised to see that AU had found the network again. I then kicked off the upgrade to the Capsule and everything went perfectly.