Dell precision M4700: Wireless failed after ubuntu 12.04 updating

[rbaena]

Hello everybody,

hope somebody can help.
I am working on a Dell precision M4700 laptop with Ubuntu 12.04 and KDE desktop.
After a "suggested" system updating, my wireless connection stops working. KNetWorkManager sees the wireless and tries to connect to it but, after a while, a small windows pops up and asks for a password. If I introduce the wireless one I have it tries again but nothing happens. That window appears again and again asking for a password.
Such windows has a key as a symbol on the top left corner, the same key appears over the KNetWorkManager symbol which is on the bottom panel. The window has the title "Secretas de [wireless name] - Service for KDE-" (in Spanish sorry ).

I guess some security measurement has been activated after the updating but I do not know how to deactivate it.

I am sure the password is correct and the router is working fine, indeed, I am using another laptop to publish this thread using the same wireless connection.

I also post some useful information:

kernel: 3.2.0-37-generic
desktop KDE
ubuntu 12.04.2 LTS

iwconfig:

lo: no wireless extension
eth1: IEEE 802.11abg ESSID off/any
Mode: managed access point: not-associated
Retry long limit:7 RTS thr off Fragment thr off
power management: off
eth0: no wireless extension

Thanks for your support!

[chili555]

Please see your question at askubuntu.com.

[Merrattic]

Which is here: http://askubuntu.com/questions/25637...12-04-updating

Try turning the hardware wireless switch off if you have one? On my Dell Precision M6500 I have to have it on for W7 but off for Xubuntu 12.04.2.

[rbaena]

Thanks for your answer.
I do not see any hardware switch to set off the wireless device. Where is it?

[chili555]

Please see #13 attached.

[rbaena]

Thanks, I tried switching off the button #13 but it does not work either.

[chili555]

Please move the switch to ON and open a terminal and run and post:

rfkill list all

Move the switch the other way and run and post again:

rfkill list all

[rbaena]

Hi, I tried the following:

hardware switch on
rfkill list all

0: dell-wifi: Wireless LAN
Soft blocked: no
Hard blocked: no
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: brcmwl-0: Wireless LAN
Soft blocked: no
Hard blocked: no

Then, hardware switch off
rfkill list all
0: dell-wifi: Wireless LAN
Soft blocked: yes
Hard blocked: yes
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: brcmwl-0: Wireless LAN
Soft blocked: no
Hard blocked: no

Finally I set the switch on again.
The wireless is still not working. It sees the home LAN and tries to connect again and again but it does not.

[chili555]

hardware switch on
rfkill list all

0: dell-wifi: Wireless LAN
Soft blocked: no
Hard blocked: no
1: phy0: Wireless LAN
Soft blocked: no
Hard blocked: no
2: brcmwl-0: Wireless LAN
Soft blocked: no
Hard blocked: no

At this point, we know the switch is not stopping your wireless. Let's troubleshoot the wireless device itself. Please run and post:

lspci -nn | grep 0280

The pipe symbol | is on the right side of my US keyboard on the same key with \.

[rbaena]

Here you are ip a and lpsci -nn | grep 0280

rbaena@fajnmp2:~/DataPart2/Otros$ lspci -nn | grep 0280

03:00.0 Network controller [0280]: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller [14e4:4727] (rev 01)

rbaena@fajnmp2:~/DataPart2/Otros$ ip a

1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast state DOWN qlen 1000
link/ether d4:be:d9:82:0a:99 brd ff:ff:ff:ff:ff:ff
3: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether a4:17:31:4b:52:6e brd ff:ff:ff:ff:ff:ff
inet6 fe80::a617:31ff:fe4b:526e/64 scope link
valid_lft forever preferred_lft forever