As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF AND DURING CLIMB, CREW RECEIVED RIGHT MAIN LANDING GEAR DOOR WARNING LIGHT. CREW VISUALLY VERIFIED THAT RIGHT GEAR DOOR WAS IN THE OPEN POSITION. FLIGHT RETURNED TO ATL AND LANDED WITHOUT INCIDENT. ATL MAINTENANCE REPLACED LEVEL LOCK SOLENOID. ALL OPERATIONAL CHECK GOOD.