I just got ours going again. I am not sure exactly which step cured it, but here is what I did.
1) take a flashlight and check for ANY scraps of paper or foreign objects in the paper path (I found a tiny bit of Christmas garland in mine)
2)I took a cotton swab and carefully dabbed up some of the excess ink on the foam pad below where the print head runs
3) I reset the printer as suggested by others (with the printer off, hold down the "stop" and "BW" buttons turn on the power, it will come up with a message about "init eeprom", wait a few seconds, then turn the power back off
4) reset again, this time holding down the "stop" and "color" buttons while turning the power on
The print head ran back and forth a few times, then the regular menu came up with no error!
I hope this works for you.