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I've somehow managed to disable my wifi a few days ago. Now the laptop doesn't seem to be able to relate anything to wlan0.

[the hardware switch is on, and I don't have a windows to check if it works there.]

Here are outputs of some commands that might help:

For ifconfig

eth0      Link encap:Ethernet  HWaddr 00:1b:24:80:63:03  
          inet addr:  Bcast:  Mask:
          inet6 addr: fe80::21b:24ff:fe80:6303/64 Scope:Link
          RX packets:218095 errors:0 dropped:0 overruns:0 frame:0
          TX packets:71280 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:311077218 (311.0 MB)  TX bytes:6798891 (6.7 MB)
          Interrupt:45 Base address:0x8000 

lo        Link encap:Local Loopback  
          inet addr:  Mask:
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:2996 errors:0 dropped:0 overruns:0 frame:0
          TX packets:2996 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:244647 (244.6 KB)  TX bytes:244647 (244.6 KB)

And for sudo ifconfig wlan0

wlan0: error fetching interface information: Device not found

Also for sudo ifup wlan0

Ignoring unknown interface wlan0=wlan0.

And finally, sudo lshw -C network

       description: Ethernet interface
       product: RTL8101E/RTL8102E PCI Express Fast Ethernet controller
       vendor: Realtek Semiconductor Co., Ltd.
       physical id: 0
       bus info: pci@0000:03:00.0
       logical name: eth0
       version: 01
       serial: 00:1b:24:80:63:03
       size: 100Mbit/s
       capacity: 100Mbit/s
       width: 64 bits
       clock: 33MHz
       capabilities: pm vpd msi pciexpress bus_master cap_list rom ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
       configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full firmware=N/A ip= latency=0 link=yes     multicast=yes port=MII speed=100Mbit/s
       resources: irq:45 ioport:2000(size=256) memory:f0200000-f0200fff memory:a0800000-    a081ffff
      *-network UNCLAIMED
       description: Network controller
       product: PRO/Wireless 3945ABG [Golan] Network Connection
       vendor: Intel Corporation
       physical id: 0
       bus info: pci@0000:04:00.0
       version: 02
       width: 32 bits
       clock: 33MHz
       capabilities: pm msi pciexpress bus_master cap_list
       configuration: latency=0
       resources: memory:f0300000-f0300fff

The output of lspci for my network controller is:

04:00.0 Network controller: Intel Corporation PRO/Wireless 3945ABG [Golan] Network Connection (rev 02)

So I tried sudo apt-get install linux-backports-modules-* but it's still the same!

share|improve this question
Do you get any clues when you load the driver? sudo modprobe iwl3945 If so, please edit your question to add the error message here. – chili555 Feb 19 '13 at 21:40
This is the warning I get "WARNING: All config files need .conf: /etc/modprobe.d/blacklist, it will be ignored in a future release." – Keivan Feb 19 '13 at 23:18
up vote 2 down vote accepted

It seems your device is hard or soft blocked.

I would try rfkill unblock all. If it is not a question of drivers, this should re-enable your wifi.

share|improve this answer
Thanks a lot, that worked like a charm. – Keivan Feb 19 '13 at 23:18
Would you mind giving me some more information about what had happened please? – Keivan Feb 19 '13 at 23:19

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