As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOS INFLIGHT - LEADING EDGE SLAT DISAGREE INDICATION WHEN FLAPS SELECTED TO ONE AT 21 KNOTS. LANDED BOS WITHOUT INCIDENT. FOUND NUMBER ONE SLAT AND NR 2 ROTARY ACTUATOR TRIPPED. REPLACED NR 2 SLAT ROTARY ACTUATOR. SYSTEM GROUND CHECKED NORMAL OPERATION.