Check printer in canon image class d760

This sounds very much like you might have snapped one of the corotron wires...these are very thin wires that apply a charge to the surface of the drum.
they run from the front to the back of the machine just under where the drum cartridge is.the paper passes over it ...you should see a little channel where it should be.

Moisture in paper may cause your copier to jam. To eliminate this problem always reseal the paper package if you don't use the entire ****.Once you have a paper jam, make sure you clear the jammed paper properly.

There may be a hardware side problem in the printer- scanner, Have you tryed unpluging it for a while and trying again?

Scanner bulb or mirrors of scanner must be having some dust on it.its easy to open the upper glass unit of scanner,jst open it carefully n clen the bulb ,mirrors n the calibration strip(black n white strip below the copier glass)with moist cloth.n refit it simply .ur copier will start copying for sure.feel free to ask 4 further asssistance.wish u success.