Ubuntu – How to fix “Wireless network disabled by hardware switch”

Well, I had installed Ubuntu 13.10 on a new machine but messed my network setting up.

1. I installed gksu

2. I ran

   gksu gedit /etc/network/interfaces
   

3. Edit the file with:

   # 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
   
   # This is a list of hotpluggable network interfaces.
   # They will be activated automatically by the hotplug subsystem.
   # auto eth1
   
   # iface eth1 inet dhcp
   

   then just save it.

4. Just to make sure everything is ok

   please check your dhcpd.conf file found in /etc/dhcp/dhcpd.conf to make sure

   option domain-name "example.org";
   option domain-name-server ns1.example.org, ns2.example.org;
   
   default-lease-time 600;
   max-lease-time 7200;
   

   do not have # before them.

5. Now restart your system and I hope it works just like mine did.

You do not have linux-image-extra for the running kernel 3.13.0-59. The kernel module ath9k is not installed. That is probably because the upgrade had been interrupted.

You need to connect to the internet by wire and run

sudo apt-get update
sudo apt-get dist-upgrade

If that does not install the extras, you can manually install them by

sudo apt-get install linux-image-extra-3.13.0-59-generic

but this means that some dependencies are not correct.

If you can't connect by wire, then boot with one of the previous kernels using grub menu. The wifi should work.

Then run the same commands.

Another option is to switch to 3.19 kernel by running

sudo apt-get install linux-generic-lts-vivid