If there is no margin, or if there is a solid image area near the leading edge of the original, make a margin of at least 5 mm (0.2 inches) at the leading edge. Otherwise, the paper exit pawl may become dirty and cause black lines to appear on the prints.
Check the exposure glass cover and clean it if it is dirty. See Cleaning the Exposure Glass Cover.
Check the exposure glass and clean it if it is dirty. See Cleaning the Exposure Glass.
If black lines or stains still appear on prints even after you clean the exposure glass, contact your service representative.