missing operating system

[rjvana]

last night I fired up my back up pc and got this message( missing operating system). No mater what I do or did I cannot get it to boot up. even booting to the original operating disc which is win 7 ultimate 64 . it runs a fix but when all done I get this message that this program cannot fix this computer ,how can I wipe the disc and if i cannot get it to boot.
Thank for any information

 

[Thineswar]

i know its stupid, but is your hdd (the one with the os) plugged in?
also, in your bios, is the boot drive set properly?