Hello i had the same problem with my canon pixma ip 3000 and i found
this steps to reset the printer and it work i hope it will help you in
yours.
Reset ip2000 / 3000
1. Turn off printer
2. Hold down Resume button and press Power button.
3. Keep holding down Power button and let Resume button go.
4. Press Resume button 2 times then let BOTH buttons go.
5. Green lights will flash and then stop blinking.
6. When green lights are solid, press the Resume button 4 times.
7. Press the Power button and the printer should turn off, if not,
press the Power button once more.
8. Your printer should respond as normal..
here is the link for other printers:
http://www.cyber-ink.com/member-canon.htmlSolution posted on http://www.fixyourownprinter.com/forums/laser/25975 by sguadalajara. My mp620 was printing fine at 600dpi but a 5100 error used to came up when i was trying higher resolutions. I followed the instructions above an the error disappeared. :)