As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE REAR STAIRWAY HAD BEEN EXTENDED AT SOME POINT WHEN THE ACFT WAS PARKED. WHEN THE STAIRS WERE RETRACTED THE CATWALK REMAINED STUCK IN THE UP POSITION BLOCKING THE EMERGENCY PATH, AND WAS LATER JOLTED OUT OF THAT STUCK POSITION DURING TAXI FOR TAKEOFF. MX SEQUENCED THE STAIRS CORRECTLY AND THE PROBLEM DID NOT REPEAT.