As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLIGHT 5204 - WHEN GEAR WAS SELECTED DOWN FOR LANDING AT CVG, RECEIVED A GEAR DOWN DISAGREEMENT MESSAGE. CREW DECLARED AN EMERGENCY AND ABORTED FIRST APPROACH. CREW PULLED EMERGENCY HANDLE FOR GEAR EXTENSION THEN LANDED WITHOUT INCIDENT ON SECOND ATTEMPT.REPLACED THE MLG SELECTOR VALVE.