Ubuntu 12.10 - network manager not listing wireless networks

Question

Just recently reinstalled Ubuntu 12.10 on my laptop (dual-boot with Windows 7). Had no problem accessing my home wireless network until today. All of a sudden, the network manager doesn't seem to be picking up any wireless networks. My laptop's wireless adapter is on, I can connect when I'm using my Windows 7 partition, and every other device in my house is able to connect. Why would the wireless just drop off like this? I can post the results of any commands I should run if that would help.

EDIT: here is the requested additional information:

sudo uname -a
Linux richard-HP-G62-Notebook-PC 3.5.0-18-generic #29-Ubuntu SMP Fri Oct 19 10:26:51 UTC 2012 x86_64 x86_64 x86_64 GNU/Linux

sudo lspci
00:00.0 Host bridge: Intel Corporation Core Processor DRAM Controller (rev 02)
00:02.0 VGA compatible controller: Intel Corporation Core Processor Integrated Graphics Controller (rev 02)
00:16.0 Communication controller: Intel Corporation 5 Series/3400 Series Chipset HECI Controller (rev 06)
00:1a.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05)
00:1b.0 Audio device: Intel Corporation 5 Series/3400 Series Chipset High Definition Audio (rev 05)
00:1c.0 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 1 (rev 05)
00:1c.2 PCI bridge: Intel Corporation 5 Series/3400 Series Chipset PCI Express Root Port 3 (rev 05)
00:1d.0 USB controller: Intel Corporation 5 Series/3400 Series Chipset USB2 Enhanced Host Controller (rev 05)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev a5)
00:1f.0 ISA bridge: Intel Corporation Mobile 5 Series Chipset LPC Interface Controller (rev 05)
00:1f.2 SATA controller: Intel Corporation 5 Series/3400 Series Chipset 4 port SATA AHCI Controller (rev 05)
00:1f.3 SMBus: Intel Corporation 5 Series/3400 Series Chipset SMBus Controller (rev 05)
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 02)
03:00.0 Network controller: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller (rev 01)
7f:00.0 Host bridge: Intel Corporation Core Processor QuickPath Architecture Generic Non-core Registers (rev 05)
7f:00.1 Host bridge: Intel Corporation Core Processor QuickPath Architecture System Address Decoder (rev 05)
7f:02.0 Host bridge: Intel Corporation Core Processor QPI Link 0 (rev 05)
7f:02.1 Host bridge: Intel Corporation Core Processor QPI Physical 0 (rev 05)
7f:02.2 Host bridge: Intel Corporation Core Processor Reserved (rev 05)
7f:02.3 Host bridge: Intel Corporation Core Processor Reserved (rev 05)

sudo ifconfig

eth0      Link encap:Ethernet  HWaddr 3c:4a:92:00:aa:66  
          inet addr:192.168.0.114  Bcast:192.168.0.255  Mask:255.255.255.0
          inet6 addr: fe80::3e4a:92ff:fe00:aa66/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:58290 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3475 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:7592666 (7.5 MB)  TX bytes:620983 (620.9 KB)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:3618 errors:0 dropped:0 overruns:0 frame:0
          TX packets:3618 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:590058 (590.0 KB)  TX bytes:590058 (590.0 KB

Solution 1

Do the command:

sudo gedit /etc/NetworkManager/NetworkManager.conf

This will open up that file in a text editor. Change the line that has managed= to:

managed=true

Save and close the file, then do:

sudo killall NetworkManager 

Logout and log back in again.

Solution 2

In my case, after I followed the other answer, I saw that it now showed device not ready after a reboot.

Here's what I did to fix that:

sudo gedit /etc/network/interfaces and I got a file containing this:

#This file describes the network interfaces available on your system
#and how to activate them. For more information, see interfaces(5).

#The loopback network interface
auto lo
iface lo inet loopback

#The primary network interface
auto wlan0
iface wlan0 inet dhcp
        wpa-ssid Wifi Name
        wpa-psk  Wifi Pasword

I deleted everything below # The primary network interface and after a reboot I had wireless networks available again.

Comments

[nilsonneto]

We need more hardware information to help you, can you look at this question and then edit your question adding the information.

[Richard Stokes]

@fossfreedom just added some additional info there

[Ben Lee]

Thank you! I'm not the OP, but I had the same problem and this solved it for me.

[packetie]

Thank you so much @conman253. Really appreciate your simple but working tip after spending lots of time searching for a solution.

[Wajih]

Super answer! Saved my day today at office :)