Yes, for $150 you can purchase a paper tray which will add an additional 250 sheet paper tray to your printer.
It means your paper tray is empty. Put some blasted paper in it and quit wasting time.
"Paper tray is empty" means the censor to the paper tray may need refilling or removing some paper and the printer is relaying this information backto the computer to let you know. Or there may be a fault with the printer and it needs fixing.
You can load 250 sheets in the regular tray.
A tray cover (looks like a piece of paper) or a sterilized wrapping paper used for wrapping the instrument pack.
Is the paper in the printer tray properly.
The standard paper tray capacity is 1100-sheet and it can be expandable upto 2100 sheets.
Pull the paper tray out. Open the lid. There is a light blue clip on the end. Press it and you can extend the bottom of the tray. There is a part of the lid of the tray that you can extend too. There is no clip. Just force it (gently). Then load your paper and print as normal. There are instructions printed on the bottom inside of the tray, but they are not great.
To remove the paper input tray from an HP C410a printer, first, ensure that the printer is powered off. Then, locate the input tray at the bottom of the printer, press the release latch, and gently pull the tray outward until it separates from the printer. Be careful not to force it, as this may damage the tray or the printer. Once removed, you can clean or replace the tray as needed.
It means that a computer has asked the printer to print something on Legal paper (8.5" x 14") from the upper paper tray of the printer, and the printer is now asking for the paper to be loaded so it can complete the job. Where the Upper Tray is will vary by printer model.
Gravity
For paper being scanned: put it into the document feeder. For paper being printed: put it into the paper tray.