As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW REPORTED ON CLIMB RECEIVED A FWD CARGO DOOR MESSAGE. AIRCRAFT RETURNED TO SDF AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED USING THE AIRCRAFT MANUAL AND FOUND A PROX SENSOR OUT OF RIG. MAINTENANCE ADJUSTED THE SENSOR AND CHECKED THE AIRCRAFT PER THE AIRCRAFT MAINTENANCE MANUAL. AIRCRAFT WAS REPLACED FOR SERVICE.