Strange message after BIOS Update

Question

Flashed the BIOS on a Asrock 775VM800 motherboard. On start-up the message 'mac address are invalid in both apc and flash' 'please press F1 to continue'When I press F1 the machine boots and runs normally but the message returns at each re-start.I have re-flashed the BIOS back to the version that came with the board but the message remains. I have re-set the CMOS and checked and rechecked the settings but can't see anything that seems out of place.Any suggestions?