As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AT 2500 MAIN CARGO DOOR ILLUMINATED WITH NO PRESSURIZATION ABNORMAL INDICATION. MASTER WARNING INDICATION FOR MAIN CARGO DOOR DISPLAYED. CREW ELECTED AIR TURN BACK TO DEPARTURE STATION KABE WITH AN EMERGENCY DECLARATION. LANDING WAS UNEVENTFUL WITH NO ADDITIONAL PRECAUTIONARY ACTIONS. ON ARRIVAL AIRCRAFT GROUNDED FOR MAINTENANCE.