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I have a laptop with Windows 7 and Ubuntu 12.04. I have a Cisco E1200 and when I set it up, it created 2 SSIDs. Let's name them:

  1. MyConnection (WPA/WPA2 personal), and
  2. MyConnection-Guest (no authentication, guest password entered via web browser).

I had no problem connecting to MyConnection before, either in Windows 7 and Ubuntu. But now, I can't access MyConnection on Ubuntu. It just says "connecting..." then disconnects after a while. But I'm able to access the internet (on Ubuntu) when I connect to MyConnection-Guest.

MAC filtering is off (even if it's on its MAC address is in the white list). Any idea why I'm unable to connect to MyConnection in Ubuntu? Thanks.

Update: My Ubuntu installation can connect to ANY WiFi connection (WPA/WEP/no auth), except for MyConnection. Update2: This is what "The not so easy way" returned:

Initializing interface 'eth1' conf '/etc/wpa_supplicant.conf' driver 'default' ctrl_interface 'N/A' bridge 'N/A'
Configuration file '/etc/wpa_supplicant.conf' -> '/etc/wpa_supplicant.conf'
Reading configuration file '/etc/wpa_supplicant.conf'
Priority group 0
   id=0 ssid='MyConnection'
   id=1 ssid='MyConnection'
   id=2 ssid='MyConnection'
   id=3 ssid='MyConnection'
WEXT: cfg80211-based driver detected
SIOCGIWRANGE: WE(compiled)=22 WE(source)=21 enc_capa=0xf
  capabilities: key_mgmt 0xf enc 0xf flags 0x0
netlink: Operstate: linkmode=1, operstate=5
Own MAC address: xx:xx:xx:xx:xx:xx
wpa_driver_wext_set_key: alg=0 key_idx=0 set_tx=0 seq_len=0 key_len=0
wpa_driver_wext_set_key: alg=0 key_idx=1 set_tx=0 seq_len=0 key_len=0
wpa_driver_wext_set_key: alg=0 key_idx=2 set_tx=0 seq_len=0 key_len=0
wpa_driver_wext_set_key: alg=0 key_idx=3 set_tx=0 seq_len=0 key_len=0
wpa_driver_wext_set_key: alg=0 key_idx=4 set_tx=0 seq_len=0 key_len=0
ioctl[SIOCSIWENCODEEXT]: Invalid argument
Driver did not support SIOCSIWENCODEEXT
wpa_driver_wext_set_key: alg=0 key_idx=5 set_tx=0 seq_len=0 key_len=0
ioctl[SIOCSIWENCODEEXT]: Invalid argument
Driver did not support SIOCSIWENCODEEXT
RSN: flushing PMKID list in the driver
Setting scan request: 0 sec 100000 usec
WPS: UUID based on MAC address - hexdump(len=16): 16 3b d8 47 9e 24 50 89 96 16 6d 66 35 f3 58 37
EAPOL: Supplicant port status: Unauthorized
EAP: EAP entering state DISABLED
EAPOL: Supplicant port status: Unauthorized
EAPOL: Supplicant port status: Unauthorized
Added interface eth1
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Ubuntu is very tricky and very "delicate" when working with this kind of connections. WPA, WPA2, WEP... etc...

Assuming that you've already checked your /etc/network/interfaces.conf and all is correct,

You have 2 ways. The Easyone and the not so easy one:


Just Edit your connections . Up in the left side of the volume icon. There, select your wireless connection and just delete it. At this point I'd suggest a restart(For both, your pc and your AP). Now, when you pc turns on, try to connect to My connection and procceed normally.

That should work.. sometimes you have to wait a while but it works the most of the times.


Now. The not so easy way

I like to use command line. So, if you are not used to it.. well.. this way won't be so fast.. but you can learn a lot.

With this method you will be working with a file called wpa_supplicant.conf which, as its name says, it will beg for a WPA connection.

now, With

iwlist scanning 

You can see all your available AP (Access Points)

You should see My Connection.

Make the wpa_supplicant.conf with:

linux:~# /usr/bin/wpa_passphrase SSID_HERE SECRET_WIFI_PASS_HERE | tee -a /etc/wpa_supplicant.conf

And you will get something like this as output:


..The last one is the encrypted pass which is usefull in the /etc/network/interfaces file

then, you'll need the fresh new wpa_supplicant.conf to stablish the connection with:

linux:~# /sbin/wpa_supplicant wpa_supplicant -d wext -i wlan0 -c /etc/wpa_supplicant.conf -B

-d wext is for the wireless extention -B tells the wpa_supplicant to make a background connection to prevent the wireless to disconect if the console gets closed.

After that, you should have a fress active connection.

Hope this helps for you. If it doesn't, let me know and i'll try to help.

share|improve this answer
Hi. Thanks for the reply and sorry for only replying now. However, both ways didn't work. The "not so easy way" returned the code I included in the Update of this question. Thanks. – d4ryl3 Feb 18 '13 at 13:49
@d4ryl3 . have you already restored your AP to fabric mode? – AAlvz Feb 19 '13 at 19:40
I'm sorry, how do I do that? The only thing I did before the 2nd way was I removed the SSIDs from my wireless networks. – d4ryl3 Feb 20 '13 at 5:06
@d4ryl3 Some AP have a button which you press 5 secs or so and it turns to fabric mode... or you can access to your AP writing in your URL. There you access your AP and look for a reset to fabric mode button. It'll probably ask for the wireless pass – AAlvz Feb 20 '13 at 18:01
Oh, you mean a reset button? No it doesn't. The only button the router has is the one for WiFi Protected Setup. Accessing didn't give me anything either. Thanks for helping on this. – d4ryl3 Feb 25 '13 at 11:55

I believe I had a similar problem. I could connect to the WiFi networks already known, but I could not connect to new networks with e.g. WPA2 security.

If I opened the Settings, Network, select Wireless. In the network name drop down, I select "Other..." In the "Connect to Hidden Wireless Network" dialogue, the Wireless security drop-down was empty, and the network dialogues generally behaved funny.

I chose to install Synapse, search for WiFi and re-installed all the already installed libraries and utilities (about ten or so).

After re-installing and re-booting, everything appeared to be working again.

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I see this is an old question but I've been struggling with this problem ever since 12.04. First in 13.04 (I skipped 12.10), then 13.10 and now 14.04.

Problem is exactly as you describe.

Found out that I had reserved an IP address for my computer in the router settings: Setup > Basic Setup > DHCP Reservation

I found my wireless network card's MAC address in the list of reserved IP addresses and removed it. Immediately when trying to connect again it worked. Just wanted to let you know if anyone else stumbles in here with 14.04 problems like this.

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