As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ON CLIMBOUT AT 10,000 MSL, A MASTER WARNING "ANTI-ICE DUCT" MESSAGE WAS DISPAYED ON EICAS WITH ASSOCIATED RED FLASHING MASTER WARNING AND AURAL ALERT. MESSAGE CLEARED 10-15 SECONDS AFTER DECLARING EMERGENCY FOR RETURN. CREW RAN ENGINES AT HIGH POWER SETTING WITH ANTI-ICE SYSTEM ON FOR 1 MINUTE IAW MX CONTROL. NO FAULTS OR EICAS MESSAGES NOTED. ACFT RTS IAW MM 30-12-00.