Error message at boot up

>-----Original Message-----
>Fairly new Sony computer now shows an error message at
>boot up; a few clicks on "Cancel" allows it to boot, but
>I would like to know what is wrong. Can anyone help an
>old man with this? Message is as follows:
>"There is no disk in the drive. Please insert a disk into
>drive\Device\harddisk1\DR4."
>Thank you for any assistance.
>
>
>.
Does the computer try to access the floppy drive on
bootup, the light will come on and you will hear it
shudder. It maybe that your bios is set to boot from
drive A first. Go into the bios and make sure the
computer is set to boot from C first, or whatever letter
your harddrive is.