What was found
SHORTLY AFTER TAKEOFF, ENROUTE, CAPTAIN REPORTED A LOUD NOISE COMING FROM UNDER THE INSTRUMENT PANEL. HE ALSO REPORTED THE AIRCRAFT WOULD NOT PRESSURIZE. FLIGHT RETURNED TO FIELD AND LANDED WITHOUT FURTHER INCIDENT. FLIGHT TAXIED TO GATE UNDER OWN POWER. NO EMERGENCY WAS DECLARED. MAINTENANCE FOUND THE FORWARD E AND E COMPARTMENT DOOR OPEN. CLOSED AND SECURED DOOR. VERIFIED PROPER OPERATION OF BOTH E AND E COMPARTMENT DOOR WARNING LIGHTS. WARNING SYSTEM CHECKS GOOD.