If your printer is on your network and has an IP address, I would try entering the IP address into a web browser and clicking on Properties. Once you're logged in, go to General Setup -> Paper Management -> Tray Content & Settings. Within this menu, I would verify that all paper trays are set to "Fully Adjustable". Once this is set, you can open and close the paper trays and change the size.
bye for now.
I searched our knowledge base and it sounds like you have tried everything already, so it would be a hardware escalation:1-800-835-6100.
Somehow the paper size for the bypass tray (tray 2) on my Workcentre 6515 got stuck on A4 and I can not change it. When I pull it up on the printer itself and try to touch the paper size, nothing happens. I tried to change it from the app on my computer (Windows) and nothing happened. It doesn't bring up a menu for me to change the paper type or size. I have tried loading paper and then hitting it, nothing. I tried taking the paper out, nothing. I've tried the tray setting on "bypass" and on "fully adjustable," neither let me change the paper size. I don't know what else to do and the printer is completely frozen up now from trying to print an incoming fax. I can't even make a copy or print anything from the computer. Please help!