I'm using Ubuntu 12.10 and I can't connect to a specific password-protected wifi network. I have the password and I can connect to it with success in the same laptop with Windows 8.
I can connect to other wifi networks using Ubuntu, so it seems that this specific network is different somehow in a way that Ubuntu fails to connect to it.
When I try to connect it stays in "connecting" state for a long time (2-5 minutes) until it fails with "Connection failed: activation of network connection failed" error.
How can I fix this?
There are some issues with certain manufacturer implementations of the wireless N standard that doesn't play nice with Linux. Also sometimes having wired ethernet up can interfere. I wrote a quick script that I placed into my public GitHub repository that fixes this on most people's systems. You can find it here: https://github.com/FreedomBen/handy-bash-scripts/blob/master/fixTheInternet.bash
Run that script each time you boot up, and your wireless should work well. It will be limited to G speeds, but that's still really fast.
If you'd rather run the commands in a terminal yourself, here they are. The script is handy though because you can just run it everytime you boot and you don't have to remember these commands: