As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE TAKEOFF WAS SAFELY ABORTED AT 80 KTS AFTER THE FLIGHT CREW RECEIVED AN EICAS MESSAGE THAT THE LT FWD ENTRY DOOR WAS NOT CLOSED SECURELY. THE ACFT CLEARED THE ACTIVE RUNWAY AND TAXIED BACK WHERE MX WAS ABLE TO COMPLETE A THOROUGH CHECK OF THE DOOR AND INDICATION SYS. THE DOOR WAS VERIFIED CLOSED AND THE DOOR WARNING SYS WAS PLACED ON MCO. ACFT RETURNED TO REVENUE SERVICE.