As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON DEPARTURE GEAR UP DISAGREE WARNING. NOSE DOOR OPEN MSG RAN QRH GEAR DOWN & LOCKED RESULTED. GEAR PINNED AT THE GATE ALL 3 IAW MX REQUEST. (ACFT RETURNED TO DEPARTURE AFTER T/O -- EMERGENCY DECLARED) ADJUSTED NLG CENTERED EXTENDED PROXIMITY SENSOR IAW AMM 32-61-05. RETRACTED AND EXTENDED GEAR 5 TIMES, OPS CHECKS GOOD IAW AMM 32-30-00.