OS X 10.11 (El Capitan) Wifi connection problem

[NFC]

Hi there,

I installed OS X 10.11 from scratch on my mid 2011 iMac. Since then I couldn't connect to the Wifi of my RT-AC68U with Merlin 378.55_0 anymore. To break it down I did some tests. Unfortunately it's a bit more confusing.
First I thought there was no connection at all. However I found the connection is established for about 10 sec and then collapses.
I tried to shorten the WPA passphrase but this did help. However when I opened the Wifi without WPA encryption the connection is stable. More confusingly the connection to the Guest Wifi with WPA encryption is stable also.

I have couple more Macs in my network still on Yosemite without problems and the iMac before El Capitan had no connection problem either. As a workaround I connect the iMac to an old Airport at the moment, which is showing no problems.

I am very puzzled with this behavior. Can anyone help why my iMac isn't able to connect to my Merlin router.

Regards

 

[sfx2000]

Go into Network setup, turn off WiFi, delete the profile and reboot - creating a new profile afterwords should work...

Worse case, might have to go into Keychain access to remove the old WPA2 key...

 

[NFC]

Hello sfx200

Thanks for the reply.
I created a new profile and deleted the password from the keychain and iCloud. Unfortunately this didn't help.

I didn't not change my WPA passphrase, just for a quick test, and all my other iCloud connected Macs have no problem to connect and use the Keychain entry.

 

[sfx2000]

You wouldn't be using the iCloud keychain would you? If so, try disabling that by logging out of iCloud and repeat the steps.

 

[NFC]

You wouldn't be using the iCloud keychain would you? If so, try disabling that by logging out of iCloud and repeat the steps.

I don't see why the iCloud keychain has anything to do with it as the connection is established for about 10 sec. So the Wifi passphrase is accepted from the router. Also I had no problem with it before OS X 10.11 with or without iCloud. Please explain why you think the keychain is the problem.

 

[sfx2000]

iCloud Keychain override local keychain if enabled, and the passphrase is saved...

Just disable iCloud temporarily and give it a try... the 10 seconds means that you're eventually failing the WPA2 handshake - e.g. likely suspect here is a corrupted entry on the client side.

 

[NFC]

I disable the keychain in the iCloud settings. Delete the local entries in the keychain and did a reboot. It did not change the behavior.
Please note I did not change the passphrase at the router. So whatever was and is in iCloud is correct for a while.
Any other suggestions?

 

[kvic]

No really but have you tried rebooting AC68U?

Perhaps the WPA auth process on the router died..

 

[NFC]

Yes, did that also.
Please note that I can connect to a guest network. So I assume the WPA auth process must be fine.

 

[kvic]

Change SSID and reboot..any luck with that?

 

[mattiL]

Have you checked OS X Console app for any relating error messages?
It can be a bit hard to read it..

 

[sfx2000]

Pretty weird... I don't think this is an Asus issue, but most likely a bug in El Cap...

One other thing to try - and this would rule out perhaps any issues with the main account (local keychain and iCloud) - create a new user account without iCloud, and see if that changes things - if there is still a problem, then it's OS specific, if it allows you to login to WiFi, then it's something on that user account directly.

 

[john9527]

I have a vague recollection of a similar problem when the region set in the OS X driver didn't match the router (or wasn't set at all). Just an idea for something to check....

 

[highwire]

Pretty weird... I don't think this is an Asus issue, but most likely a bug in El Cap...

I'm inclined to agree. I have two MacBook Pros running El Cap. One is a wireless N and the other wireless AC. Both of them suffer from the same symptoms:

0) Reboot router.
1) Connect to 5GHz network OK - full speed (300 for N, 1150 for AC).
2) Speed degrades until it is painfully slow, then stops altogether.
3) Can't connect to the 5GHz network at all.

I have to reboot the router (not the computer) for the connection to return.

I have a Mac mini running the previous version of OS X and still works just fine.

 

[sfx2000]

I have a vague recollection of a similar problem when the region set in the OS X driver didn't match the router (or wasn't set at all). Just an idea for something to check....

Similar to this?

http://www.mikealbano.com/2014/03/80211d-why-you-care.html

I don't believe that OP's issue is related to 802.11D

If I recall, some time back, 802.11D support was depreciated on the client side - and FCC published rules effect Jan 1st 2015 specific to client support there... that was before the PRM affecting 3rd party firmware...

Ref for 11D FCC ruling and timeline

reference, please view KDB’s at:

https://apps.fcc.gov/oetcf/kdb/index.cfm

Under KDB Publication Number Search, enter “594280”

• 594280 D01 Configuration Control v02r01
• 594280 D02 UNII Device Security v01r01
• 926956 D01 U-NII Transition Plan v01r02

 

[Jobine]

I have a Retina MacBook Pro (Late 2013) with El Capitan and a router Asus RT-AC3200 with WPA2 and I have no problem.

 

[NFC]

I found a workaround. I created a new guest network and allowed access to the normal network. Then I connected my iMac to the new guest network. For a workaround it is working so far.
I still believe it is something wrong with the firmware because I can connect to the guest network which has basically the same configuration as the normal WiFi.

 

[kvic]

I found a workaround.

I would replace the stock Atheros 802.11n wifi card with a BCM94360CD. You will get stunning 802.11ac 3x3. BT 4.0 for continuity and handoff as a bonus.

Zero wifi issue once get rid of the old Atheros card...

 

[bodean]

I would replace the stock Atheros 802.11n wifi card with a BCM94360CD. You will get stunning 802.11ac 3x3. BT 4.0 for continuity and handoff as a bonus.

Zero wifi issue once get rid of the old Atheros card...

Is this simple to install on a 2015 iMac?

 

[sfx2000]

Is this simple to install on a 2015 iMac?

the 2015 imac already has that card