In order to fix a printer that is not picking up paper from the tray, the following steps should be taken:

1. Ensure the paper tray is completely filled with the correct paper.
2. If a multi-purpose tray is available, use it in conjunction with the primary tray.
3. Inspect the tray for any paper jams that may be present.
4. Clean the paper roller with a lint-free cloth.
5. Check that the paper size switched is correctly aligned.
6. Disconnect the power cable and USB cable, then reconnect them both.
7. Adjust the tray paper guides to better accommodate the paper.
8. Check for any loose cables in the tray that may be causing the problem.
9. Power the printer off and then back on again.