A technician has racked a new access switch and has run multimode fiber to a new location. After installing an extended-range 10Gb SFP in the core switch, the technician installed a 10Gb SFP in the access switch and connected the port to the new extension with a fiber jumper. However, the link does not display, and the technician cannot see light emitting from the core switch. Which of the following solutions is MOST likely to resolve the problem?