As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
MAIN CABIN DOOR WOULD NOT OPEN UPON ARRIVAL. THE DOOR LOCK PINS WERE FROZEN DUE TO MOISTURE & COLD TEMPERATURE WHILE ENROUTE. DUE TO PAXS MEETING & SCHEDULE THE EMER EXIT DOOR WAS USED. PAXS WERE ASSISTED BY CREW. REMOVED STANDING WATER IN DOOR FRAME. ALL DOOR MOVING PARTS WERE LUBRICATED. DOOR OPERATION WAS NORMAL. ACFT WAS RETURNED TO SERVICE.