If anyone else want's to know the same thing, you head over to usercontrol on the MFP's web interface. Create an authoritygroup that is not allowed to copy in colors, and create a default user in this group that will always be logged in on the MFP. Then create a group that is allowed to copy in colors and add a user to this group. Now you'll jut have to log in on the MFP with this user to copy with colors.