As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
GEAR DISAGREE AND NOSE DOOR OPEN MESSAGES UPON GEAR RETRACTION, PERFORMED QRH PROCEDURE AND RECEIVED 3 GEAR DOWN AND LOCKED INDICATIONS. (ACFT RETURNED TO DEPARTURE) SENSOR TO TARGET ADJUSTMENT OF NLG. CENTERED EXTENDED PROX SENSOR REF AMM 32-61-01.