What was found
CREW REPORTED GEAR DISAGREE RED CAS MESSAGE AFTER TAKEOFF. MAIN GEAR INDICATION WAS WHITE BOX AND NOSE GEAR STAYED GREEN. CREW RETURNED TO FIELD AND LANDED WITHOUT INCIDENT. MAINTENANCE INSPECTED AND FOUND NOSE GEAR DOORS OPEN WITH SWITCH BETWEEN OPEN AND CLOSE POSITION. MAINTENANCE RETURNED SWITCH TO NORM / FLT POSITION AND PERFORMED GEAR SWING USING AIRCRAFT MAINTENANCE MANUALS. AIRCRAFT RELEASED FOR SERVICE.