As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CRUISE, CREW DOOR BLEW OPEN CAUSING THE ACFT TO DEPRESSURIZE. DECLARED AN EMERGENCY, DESCENDED, AND RETURNED TO POINT OF TAKEOFF. A SAFE LANDING WAS MADE. ON INVESTIGATION DOOR WAS FOUND TO IN THE LATCHED-LOCKED POSITION. AS OF YET NO REASON FOR FAILURE HAS BEEN DETERMINED.