What was found
AT FL 360 RECEIVED A MC LIGHT AND AMBER EICAS ALERT, MAIN CARGO DOOR. DESCENDED TO 10,000 FT IAW QRH. ALERT EXTINGUISHED AFTER PRESSURE EQUALIZED DURING DESCENT. EMERGENCY DECLARED. RELEASED FOR SERVICE IAW MEL : 52-71-01-02. VERIFY AND RECORD IN AML/EAML THAT MAIN DECK CARGO DOOR IS CLOSED, LATCHED, AND LOCKED BEFORE EACH DEPARTURE." AT BLOCK IN MCD VERIFIED CLOSED, LATCHED AND LOCKED. CYCLED DOOR. NORMAL OPERATION.