As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON TAKEOFF AT 70 KTS MAIN CARGO DOOR WARNING WITH EICAS MSG. MASTER WARNING HORN SOUNDED. REJECTED TAKEOFF & MESSAGE CLEARED, SECOND ATTEMPT WAS GOOD WITH NO INDICATIONS PRESENT. ENTERED PER CA 219512 AMM: 52-32-00-5-0 AMM: 05-51-14-14-2 PERFORMED OPS CHECK OF MCD PER AMM 52-32-00-5-0, OPS CHECK NORMAL. NO DAMAGE OR EVIDANCE OF POSSABLE HIGH ENERGY STOP PER AMM 05-51-14-14-2. OK FOR SERVICE.