As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON FLIGHT 4257 THE CREW REPORTED THEY COULD NOT OPEN THE MAIN CABIN DOOR FROM INSIDE THE CABIN. THE AIRCRAFT WAS REMOVED FROM SERVICE. RESECURED MAIN DOOR HANDLE PER EMB-140 MM 52-11-01. THE OPERATIONAL CHECK WAS GOOD. THE AIRCRAFT WAS RETURNED TO SERVICE.