I've used the MSI Forum Flash Utility program to prepare a USB stick for a BIOS flash under Vista64, the stick contents look fine to me, but when trying to boot from the stick (selecting the flash disk from the BIOS boot menu), the system says
'Missing Operating System'
so the system apparently can't boot from the stick while the Flash Utility program doesn't seem to indicate an error while preparing the stick.
Does somebody have a clue ?
The stick is a 1 GB FAT volume and contains the regular command.com and BIOS file.