Can't connect to wifi networks

Are you sure the network you're looking for is up? Can you connect to it using some other device?

What's havlet? If it's proprietary software which we disapprove, don't link to it.

If you messed around with blacklisting drivers and things like that then its possible you disabled the driver. You might have done this if you were attempting to load a MS Windows driver via NDISWrapper for instance- or had some other conflict. We highly recommend people not use this software for a variety of reasons. Besides the fact your probably (almost certainly actually) loading a non-free piece of software with it the solution itself is a security and stability nightmare. It won't just be the wifi crashing, but your entire system. It is a hack that probably shouldn't have ever been produced. It creates all sorts of problems and even if you think it is perfectly stable it can create problems elsewhere- for instance when you later go to use another piece of hardware, or proper support comes about with a kernel update, etc.

There are also some other things you might have done by accident. If its a laptop for example there may be an on/off button. Sometimes it is a physical switch, but more often than not it is a FN key plus one of the F1-F12 keys.

Another possible issue is if you switched USB ports and there are more than one USB controller. This tends to heavily depend on the controller, kernel version you have, etc. The problem is there are some systems which have multiple controllers and depending on the driver its using there could be a problem related to one of them.

I found what might be causing the problem. My system recently upgraded kernel to 3.15.4-gnu (linux-libre from jxself repository). Well I found out that if I load the 3.14.6-gnu there is no problem, I can connect to any wifi network, while if I load any 3.15 version, it won't work with any password-protected networks.

Just in case anyone ask me why I'm using that linux-libre version, it's because my laptop usb port wasn't supported by the default version 3.2 (I think it was you, Chris, who suggested that solution to me by email when I bought the USB adapter).

If this is the issue, what should I do, wait for newer versions of the kernel? Will it possibly be fixed in the future?

By the way, lembas, I think havlet is not proprietary since I found it in trisquel's repositories. If it actually is proprietary, who should I contact to remove it?

Thanks a lot.

Thank you jxself, I'll contact you.
Lembas, sorry, it was halevt...

I've confirmed an issue exists with the 3.15.x kernel and have added a temporary fix to the support documentation @ ThinkPenguin.com/support. Besides reverting back to an older kernel you can simply make the following modification:

1. Run the following from a terminal window:

sudo nano /etc/modprobe.d/ath9k_htc.conf

2. Add the following line and save:

options ath9k_htc nohwcrypt=1

3. Reboot

Your wireless adapter should now be working again.

* This is only applicable if you have a distribution with the 3.15.x kernel and/or have manually upgraded to this kernel (ie are using the latest stable series kernel from jxself's linux-libre repository).