I jusy installed Ubuntu 12.04 and had a lot of problems getting the WiFi to be recognized. But even as I solved that issue I cannot yet get connect with my WiFi, as my (100% sure) correct password is not accepted and the system keep asking me for the password. Anybody here could help? Thnks a lot!
Try installing any Updates to Ubuntu and if that doesn't work try using Ubuntu 13.10. I had the same issues until the system was updated.
An alternate suggestion that you boot into Ubuntu with a different version of Linux, you should be able to do this from booting up the computer and then selecting "Advanced Options for Ubuntu" and selecting another version to boot into.