As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TROUBLESHOTING OF THE FLAP ISOLATION VALVE EICAS MESSAGE, THE LEFT INBOARD FLAP TRACK FORWARD SUPPORT FITTING HAS FOUND TO HAVE LOOSE OR BROKEN HARDWARE. REMOVED AND REPLACED THE LEFT INBOARD TRAILING EDGE FLAP TRACK SUPPORT BRACKET IAW AMM 27-51-03. OPERATIONAL CHECK GOOD. AIRCRAFT WAS GROUNDED.