As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMB, AIRCRAFT WOULD NOT PRESSURIZE NORMALLY. CREW NOTED SQUEAL AT L1 DOOR. AIRCRAFT RETURNED TO MSP AND LANDED WITHOUT INCIDENT. FOUND L1 DOOR JAMMED. OPENED AND INSPECTED L1 DOOR. CYCLED DOOR SEVERAL TIMES. OPS CHECK GOOD. AIRCRAFT PRESSURIZES NORMALLY. NO OTHER DEFECTS NOTED. AIRCRAFT RETURNED TO SERVICE.