Airport Express N Spec Fails to see 5ghz Timecapsule signal

I had the same problem.
After the update restarting the computer or waking up from sleep my base station was only able to see the g signal. Checking with iStumbler I could see the dual bands but in order to join the 5 GHz I had to turn Airport off and then back on.
No change in the Time Capsule settings. The only difference I found was the appearance of channel 100, that even if is among those included in the european specs I never have been able to join, other than channels 36,40,44,48.
Resetting the base made no difference.
The only way was to revert back to 7.4.2 and everything is now fine.

Same here....
And it's impossible to join the guest network, with password protection (wep, wep/wep2, wep2).
Installing back the 7.4.2 make it works again as before....

What security are you guys using on your Base Stations ? Try WPA2-AES.

Do you guys have your Base Station set to advertise a different SSID in 2.4 and 5Ghz mode ? Or is it advertising the same SSID ( network name ) in both modes ?

You should be able to specify this under Wireless->Wireless Network Options in AirPort Utility.

wifiguru, thanks for your suggestion.

As far as the security I am using WPA2 Personal and I have the same SSID in both modes.

I had a very similar problem, I'm running an AirPort Dual-Band II

I wanted to have my MBP unibody connect on the 5 GHz & my old MBP & iMac on the 2.4 GHz to reduce traffic.

Under version 7.5.1. I set both frequencies to Auto channel selection & connected... But each time my MBP went to sleep or I restarted it it would then reconnect to the 2.4 GHz network.

Both have the same network name but I added a 5 to the end of the 5 GHz so I knew which one was connecting.

After having a replacement base station supplied & a couple of very long calls to Apple we managed to identify what was causing the problem. If I set the 5 GHz to manual channel selection & selected one of the available channels eg.44 all works perfectly, my MBP hooks up to the 5 GHz network every time without fail... set the channel to auto - up in the hundreds it would select the 2.4 GHz & I would have to manually log in to the 5 GHz each time.

I've just updated to version 7.5.2 but not yet risked changing the channel setting back to auto!

Give it a try & see if it works for you...

Good luck

Thanks anb!

I previously made a manual selection but only for the 2.4 GHz and now I did a manual selection also for the 5 GHz. It works! My Time Capsule now connect on the 5 GHz as prior the update.

What I am curious to know is why after the update with the automatic selection channel 100 is selected by default and now I cannot see it anymore.

Thought they would have fixed this problem in 7.5.2 the bug was supposed to have been escalated back in May this year...

As to why you can't see the high channel numbers in auto for the 5 GHz... I don't have a clue & neither did the Apple network guy I spoke to in May...

anb,
The mid band channels ( 52-64) and the higher and upper band channels ( less than 149) are known as DFS channels. When a wireless device picks one of these channels to operate it is expected to check for radar signal's ( for 60 seconds) and then pick the channel if no radar is detected. Else it moves to another channel. If this second channel is also a DFS channel, then the AP takes longer to come up.

Channels 36-48 don't have this issue. Which is why picking a channel in this range works. You will find that if you test in a shielded environment the upper channels will also work fine.

It appears you live in a area where radar signals are present, hence you see this issue.

wifiguru
Not going to disagree with you, but given I live down in a valley high up in the Pennines the chances of a local strong radar source are zero... unless it's above me!

Secondly the issue wasn't that it wouldn't select a channel but that my MBP wouldn't select the 5 GHz bandwidth when connecting to the AirPort, it would immediately select the 2.4 GHz connection if the connection details were also stored in my network settings, if they were not, then the MBP would make no connection to the AirPort unless I manually entered the 5GHz ID & password each time I logged in or started up.

Taking what you say along with what happened only goes to highlight that this is a bug if AirPort is doing this checking as you describe.

I also had success by changing the mode from automatic to manual, and selecting the channels.

Thank you to all who posted, I had struggled with this same problem for hours and am now finally getting traction with manual channel selection.

Thank you anb!
Plagued by the same symptoms (MBP Unibody unwilling to re-connect to the 5 GHz net of a Dual-Band AEBS), setting the channel to 36 instantly solved the problem.
In the unlikely event that the software engineers in charge for the firmware look this up with a view to solving this, I wonder what is the best way to report it, as Apple has no standardised bugs reporting mechanism for the end-user, though.
Any ideas?

Happy this works for other users... you can always bombard Apple with bug reports through

http://www.apple.com/feedback/

Select the product & fire away... it's like banging your head against a brick wall and you have to assume someone at Apple reads the postings!

Have a Great Christmas all...

If i change the setting on the Airport Extreem to channel 44, do i also have to change the channel setting on my Airport Express? Thanks