As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 6508 - IAD-BOS - DURING TAKEOFF, MADE AN UNSCHEDULED LANDING DUE TO ON GEAR RETRACTION, GEAR HANDLE LIGHT CAME ON, RECYCLED NO FIX. AIRCRAFT RETURNED TO GATE WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND REMOVED AND REPLACED UPLOCK MICROSWITCH, OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)