As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CLIMBING THROUGH 10,000 FT, RECEIVED CABIN ALT CAUTION, FOLLOWED BY CABIN ALT WARNING MSG. EMERGENCY DECLARED, A/C RETURNED TO JAX LANDED SAFELY. INSPECTED A/C AND FOUND CARGO DOOR NOT CLOSED CORRECTLY. RECLOSED CARGO DOOR AND PERFORMED PRESSURIZATION CHECK. OPS CHECK GOOD.