I have changed all ink cartridges on my canon pixma ip4200 printer and it now doesn't work, the green and amber lights flash for 11 times and the cartridge carrier doesn't move. Please can someone advice what to do to resolve. Thanks

From Canon Help Files.

Automatic Print Head alignment failed
Possible causes are as follows:
A4 or Letter-sized paper is not loaded on the Auto Sheet Feeder.
Press the RESUME/CANCEL button on the printer to clear the error, then load one sheet of A4 or Letter-sized paper in the Auto Sheet Feeder.
Automatic print head alignment cannot be performed using paper from the Cassette. For automatic print head alignment, always load paper in the Auto Sheet Feeder.
Print Head nozzles are clogged.
Press the RESUME/CANCEL button on the printer to clear the error, and then print out the nozzle check pattern to examine the print head condition.

For information on how to print a nozzle check pattern, see "
The Paper Output Slot has been exposed to a strong light source preventing correct Print Head alignment.
Press the RESUME/CANCEL button to clear the error and move the printer to a darker location.
After carrying out the above measures, if the problem continues after aligning the Print Head again, press the RESUME/CANCEL button to clear the error, and then perform manual print head alignment. For details on manual print head alignment, see "Manual Print Head Alignment."