As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON INITIAL CLIMB, CREW RECEIVED A GEAR DISAGREE MESSAGE ON TAKEOFF WITH THE GEAR HANDLE IN THE UP POSITION. CREW RAN THE QRH AND RETURNED TO THE NEAREST SUITABLE AIRPORT. MAINTENANCE REMOVED AND REPLACED LANDING GEAR HANDLE AND PSEU. PERFORMED GEAR SWINGS AND OCF, OPS CHECK GOOD.