Hello, all--

I'm running Ubuntu 16.04 on a dual boot Dell Inspiron 1535. I started setting up a VPN on my laptop a week ago, then aborted the effort, and my wifi has been down since then (I'm able to get online via my iPhone's Personal Hotspot feature). I've since uninstalled OpenVPN.

I've determined that the driver ath9k is off, but I cannot figure out how to turn it back on. I've been following instructions on various threads here & on Ask Ubuntu, using various commands to try to diagnose the problem. Tonight I ran ifconfig -a to see what my putative connections look like. Here's what I got:

I then tried this:

sudo ifconfig wlan0 up

which yielded this message:

I'd run rfkill list last night, yielding this output:

I don't know how to unblock my wireless LAN.

Please advise.

Thanks.

Your wireless card is disabled by a hardware switch. You can't do anything about it from linux.
There should be a hardware switch somewhere on your machine (sometimes it is Fn + F7, sometimes a dedicated button...). Flip that and you should be good.
Also maybe check that it isn't disabled in the BIOS/UEFI configuration.

1 members found this post helpful.

Thank you, Serafean! That did the trick! It was Fn-F2.

I'm really grateful to you--I've been banging away at this for a few days, to no avail (obviously). What a relief...

'rfkill list' shows all devices affected by the switch and whether it's a hard kill or soft kill. Hard kill is the hardware switch, soft kill is software so root should be able to change the state.

Also, I find that dual-booting Windows can frequently leave the switch in hard kill for the subsequent boot to Linux, and that, after changing the hard kill switch, it can take several boots for it to stick permanently. YMMV. (Dell Inspiron)