As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 1075 - PHL - UNABLE TO PRESSURIZE AIRCRAFT IN ANY MODE. OUTFLOW VALVE WAS CONTROLLABLE IN FLIGHT. BUT EVEN WITH OUTFLOW VALVE FULL CLOSED, AIRCRAFT WOULD NOT PRESSURIZE. MAINTENANCE REPAIRED FORWARD CARGO DOOR SEAL PRESSURIZED AIRCRAFT TO 7.6 DIFF. OPS NORMAL. (M)