As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON INITIAL APPLICATION OF T/O POWER, GROUND SPEED WAS BELOW 10KTS. L HYD DEM PUMP EICAS MESSAGE ILLUMINATED. PER QRH, THE PUMP SWITCH WAS PLACED "ON" LIGHT REMAINED OUT. TAKE OFF WAS ABORTED AND AIRCRAFT EXITED RUNWAY TO TAXIWAY.CREW CONTACTED MAINTENANCE CONTROL AND A FLIGHT CREW DEFERRAL WAS COMPLETED IAW MEL 29-11-5-1. AIRCRAFT CONTINUED ON WITH PLANNED FLIGHT WITHOUT FURTHER INCIDENCE.