Are you putting the paper on the front tray? The selphy takes the paper from the front all the way out the back before it starts printing. If it doesn't go in, you may need to clean the roller in the front with a damp towel so it can grab better.
My deskhet 842c stopped printing in the middle of the page and the bottom yellow light is flashing?...
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My deskhet 842c stopped printing in the middle of the page and the bottom yellow light is flashing? The ink cartridges stopped in the middlel