Here is some error codes that may be you will find when using your printer canon MP780. This error codes list will tell you what happened with your printer.

#001 TX Document has jammed
#003 TX/RX Document is too long, or page time-over
#005 TX/RX Initial identification (T0/T1) time-over
#009 RX Recording paper has jammed or the recordingpaper has run out
#011 RX Polling reception error
#012 TX The other party has run out of recording paper
#018 TX/RX Auto dialing transmission error
#021 RX The other party has rejected the machineduring polling reception
#022 TX Call fails#037 RX Memory has overflowed when receivingimages
#085 TX Other party does not support ITU-T ColorFaxing
#995 TX/RX Memory Communication reservationcancellation