Hold down the Menu button on the front of the printer for a few seconds and watch for the contrast on the LCD panel to start changing. Keep holding it down (screen will cycle continuously from light to dark until you let go) until you get to the desired contrast then let go.
I need more information. What system are you using to drive the printer with? If it is a Windows computer it is almost certain to be a faulty/outdated driver.
Your program is most likely sending codes the printer does not understand. Try a test page from your driver if that works check the settings in your program. If it fails the driver test print you may have the wrong driver installed.
