Make sure that the printer is not displaying any errors (flashing lights or error codes on the screen). If the printer is in an error state (paper jam, ink has run out, etc.) please address the error state first. Then, move to the next step.
Read a Wireless Network Settings page Signal Strength: Here you will see the strength of the printer's network connection. A signal strength lower than 80% may result in slower performance or errors when printing or scanning. If it is too low, consider moving your printer closer to your wireless router.
