Hello OliviaK,
When you get this error you will need a tech, because there is a hardware problem with the scanner. It is a possible broken scanner belt.
I am unable to scan or photocopy on my workcentre 3335. It states i need to unlock the scanner but the image it is showing of where the lock is on the printer doesnt actually have a lock. Could anyone tell me where it is so I can adjust it so that I can use the copier function again.