Sapphire X1600PRO 256MB AGP memory module showing error while update BIOS

I have a Sapphire X1600PRO 256MB AGP memory module and I tried to update the BIOS for the higher core clock speed. My problem is that once I load the New BIOS' ROM, and I click Program it says the following message, and I don't know what else to do. Is there anyone that has an idea on how to fix this?
ATIWinflash
Cannot erase ROM
