Hardware error 0502, how do I fix this? What causes it?

It happpens when the Catridge is unable to Communicate with the Printer............. In this case what i would request you to do is............... Unplug the Power Supply from the Printer When u remove the cover of the Printer behing the Catridge carrier which holds the catridges u will see a thin long transparent strip which looks like a Tap........... Take a Dry Paper Towel and Gently wipe that tape from right to the left it is very delicate so pls do it gently............ Now Take out both the Catridges from the Printer.............. Move the Catridge carrier which holds the catridge, From right to the Left and From Left to Right for abt 10 Times............... Now u can insert both the catridges in and Turn On the Machine.......... Good Luck