As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - FLIGHT 2307 - THE AIRCRAFT RETURNED TO FIELD WHEN AFTER TAKEOFF THE AFT CARGO DOOR WARNING ILLUMINATED. MAINTENANCE INSPECTED THE AIRCRAFT AND REPLACED THE HANDLE AND LATCH ASSEMBLY. OPERATIONAL CHECKS WERE PERFORMED AND THE AIRCRAFT WAS RETURNED TO SERVICE.