I'm using the correct tray (it's the little pull-out drawer at the bottom of the front of the device) and I've used it OK before (it's new). But for some reason, the paper doesn't seem to want to go in. The tray doesn't seem wide enough for the paper to lie flat without 'arching' and no amount of fiddling around with the internal slider-guides makes any difference. It's driving me bonkers. I did it OK first time without any help, because it was so obvious, and now it doesn't work. I'm baffled.
Aha! Problem solved. There are two separate drawers, one specifically for A4 paper and it's tucked away out of sight. I didn't realise this and opened the upper drawer (for smaller paper) on this occasion. D'oh! Thanks for your help.
I hope that my advising you to check the way Letter size paper fits in the drawer (and to remove the A4 paper for the moment) helped with the problem, or helped suggest the way to the solution you reached.Thank you for consulting JustAnswer.com. Please feel welcome to return at any time to ask another question in any one of our numerous categories of expertise.