getting bios error on starting windows

[chetan5]

hello guys,
one of my friend pc giving bios error. when he start his pc a black screen come up & a error displays
* bad bios checksum........starting bios recovery
* checking floppy drive
* floppy drive not found!
* checking cd rom
* cd rom not found!
* checking usb device
* usb device not found

what exactly is this & how to solve this even when i insert windows disk it's not booting.

[AzzamKhan]

Seems that your friend has tried to flash the BIOS (most probably). Because this bios error gets generated when you flash unsuccessfully. If he has tried a BIOS revision and it was unsuccessful, then there could be some corruption in the bootblock or bootloader in the BIOS program ... although it definitely looks like it is going through the proper routine.