Thank you for using the Support Forum. Please make sure you are using the Laser Waterslide paper not the kind for inkjet printers. When printing choose heavyweight glossy cardstock. Try printing from Tray 1 or the bypass tray. Take a look at the Paper and Paper Tray Specifications for your Phaser 6510. Please read the notes on printing on glossy paper located near the bottom of the paper specification web page. Also look at the article on minimizing paper jams. If it still does not work you may have to try another brand of Waterslide paper but there is no guarantee that a different brand will help.
Thanks, CherylO-Xerox Community Manager
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