My Royal MX1600 shredder will only run in reverse when you press the reverse button. When you insert paper or press the forward button the fans start up but the cutters do not move.

SOURCE: My royal 160mx shredder quit feeding paper. It

Have a look inside where you put the paper and see if the cutting blades are turning when the machine is running...if they are NOT, then you have probably broken or stripped teeth out of a gear inside...you will have to open it up to check, then you can contact Royal at 1-800-524-0799 for parts assistance.

SOURCE: Royal VF1700MX Shredder Shredder runs in reverse

Sounds like you've either lost the "eyes" or the pcb inside...contact Royal at 1-800-524-0799 for parts assistance.

SOURCE: royal sc120 shredder wont run..

This is the most common problem..."too much paper".
If it won't go in either direction the only option is to open the cutting head of the machine(after unplugging) and to manually try to turn the gears to un-clog the paper.
Once you have cleared the paper from the cutting blades see if it still turns...see if any plastic gears have been damaged. Plug it back in and see if it runs...if it dosn't you may have blown the PCB in which case you should contact Royal at 1-800-524-0799 regarding replacement parts.