As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IAH - FLT 3786 - PILOT REPORTED THE RIGHT GEAR DID NOT RETRACT. THE AIRCRAFT RETURNED TO IAH AND LANDED WITHOUT INCIDENT. MAINTENANCE REMOVED MOISTURE FROM THE RIGHT GEAR UPLOCK PROXIMITY SWITCHES. THE GEAR OPERATIONALLY CHECKED GOOD AND THE AIRCRAFT WAS APPROVED FOR RETURN TO SERVICE. (X)