Why is Firefox not working?

Hey everyone, yesterday, my normal browser, Firefox, stopped working. It's strange because there are no error messages of any sort, it just doesn't open. I then tried Google Chrome, and the same thing happened. Currently, I have no idea what is causing this, but I can tell you what I remember the last uses were. Reading the Blender manual for referance, and Registering microsoft C#. Neither of these, I would think, would cause a problem, but I may be wrong. Help please?