As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
TPA FLT 1961 CLT TO TPA - THE CREW RECEIVED EICAS MESSAGE "OUTBRD EX VAL OPEN". A BURNING ODOR WAS ALSO NOTED IN THE COCKPIT. FLIGHT LANDED WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED THE LEFT RECIRCULATION FAN. SYSTEM OPERATIONALLY CHECKS NORMAL.