Today the update-manaeger suggested that I should download some updates. So I did. After the updates were installed I had to reboot the system.
After the reboot my notebook doesn't see any wireless networks.
I was looking for a long time on the internet for answers but non of them applies to my case.
I have the idea, it has got something to do with the kernel I am currently using (Linux 3.2.0-55). Is this one new for Ubuntu 12.04?
When I boot my system I can choose to use an older kernel (linux 3.2.0-32). When I use this one the notebook does see the wireless networks.
This is my network card according to the command lspci:
Ralink corp. RT3290 Wireless 802.11n 1T/1R PCIe
Anyone an idea to fix my problems with wireless internet?