I have a Toshiba Satellite L645 laptop. I installed Ubuntu 12.04 LTS alongside with Windows 7. At first, everything worked fine. But today my Ubuntu system has a problem. It detects every wireless network in the area except my own. I found that my wireless network is 'hidden', although I didn't do anything with its settings at all. I tried to manually connect with the hidden network, but it just won't connect no matter how many times I tried.

On the contrary, when I boot Windows 7, my laptop can automatically connect to my wireless network.

How can I 'unhide' my hidden wireless network in Ubuntu and let my computer automatically connect to it every time?