As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING CLIMB THE CREW REPORTED THAT THE LANDING AIR/GROUND FAIL MESSAGE ILLUMINATED AND THE GEAR FAILED TO RETRACT. THE AIRCRAFT RETURNED TO IAH AND LANDED WITHOUT INCIDENT WHERE MAINTENANCE ADJUSTED THE MAIN LANDING GEAR PROXIMITY SWITCHES. THE GEAR WAS OPERATIONALLY TESTED AND THE DISCREPANCY CLEARED.