As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
CREW RECEIVED NR 1 ENGINE THRUST REVERSER UNLOCK ECAM MESSAGE ON CLIMBOUT. CREW DECLARED EMERGENCY AND RETURNED TO FIELD. FIGHT LANDED WITHOUT INCIDENT. REPLACED NR 1 ENGINE STOW SWITCH FIN 4104KS3 IAW AIRBUS MAINTENANCE MANUAL 78-31-00-810-863-A.