The on button stays flashing can't copy anything

This is usually an error indicating a mis-installed ink cartridge or a paper jam. It is also possible that it is a bad sensor or a driver issue, but I would re-check everywhere inside the printer first. If that doesn't work...

SOME GENERAL PRINTER TROUBLESHOOTING ADVISE:

Open the printer and remove the ink. Clean around the ink carriage and the under the ink with alcohol and a cotton swab. Check for obstruction or paper inside the printer, from behind, and underneath. You may need to remove the paper tray. With the ink, pay special attention to areas with copper contacts. Keep in mind too that some printers will not print, even with full ink, if the exact type of ink it expects you to have is not installed. Double check that the ink is correct against the manual or written instructions inside the printer. Not every cartridge that fits in the printer necessarily work.