You should have known what you can and cant do with a softmodded wii before updating. Nintendo released 4.2 to purposly brick those consoles that are softmodded. What happens when you power it up? Did you by any chance get any sd cards with the system? If so, they might have bootmii on it. Also, see if preloader is installed. When you power the system on, hold in the reset button and see what happens. If nothing happens, then you dont have preloader. Youll have to go get it fixed then.