We have a Toshiba e-Studio 452 Printer, which we use it mainly for photocopying purpose. Recently it started printing white lines in the middle of the pages. I removed the developer unit and the drum only to find out that part of the drum had Toner stack on it, i tried cleaning it with a smooth dry cloth, but the dry toner never came out, since we have a spare drum so i just went on and changed the drum, i assembled and then put back everything in place. Know when i make copies the white lines is gone but the page comes out totally dark, completely black no readable information and the drum gets covered with toner. I spent the all day figuring out what went wrong, it seems like i made it worse. I was told the problem is at the back frame of the machine a mismatch, I just don’t seem to figure it out.