I recently upgraded to 12.04 and during the upgrade installation notices my wireless signal indicator go to "no wireless". Since the upgrade, I can ONLY access the internet via a wired connection or an UNSECURED wireless connection. I do not like leaving my home wireless unsecured, however that is now my only option unless I want to go buy a 25' long ethernet cable to give me the ability to sit somewhere beside the floor near where my router is located. Any ideas as to what may have happened and/or how I can fix this bug so I can secure my home network once again?
You may try this:
Connect an ethernet cable, install updates, install Additional Drivers, reboot.
Then, open a terminal and type the following commands:
Restart again, and open up the "Network" program, and click the dropdown to select your network, and type your password.
Unplug the ethernet cable and see if you can now access your wireless network.