This question already has an answer here:
I downloaded Ubuntu 13.4 and I can only sign in as guest. I entered the User and Password I originally chose and nothing works. I can't do anything because I don't know the root password either. I run Ubuntu as well as Windows 7 Home Premium on my compaq. I'm brand new to Ubuntu and not too smart when it comes to coding. Please help if you can. And I'm not able to access the internet due to the fact I don't have the root password!