Hi,
You will want to verify that your computer sees a working hard drive
first. Pressing F2 will take you into the bios, which shows all the hardware
on the computer and its settings. You will want to see if it sees the hard
drive on one of the basic menu pages. Just look and don't change any
settings. If where it says "hard disks" nothing is listed then either the
hard disk is dead or there may be a loose connection to it so it doesn't
register.
If the disk name is displayed then at least it's partially working and
you may either have a virus or the formatting may be copput to the point you
would have to reformat and reinstall the OS (operating system).
If you don't see anything registered and know what a hard disk looks
like then you may want to check to see that both the data cable and power
cable are connected tightly to the hard drive. You can do this by first
exiting out of the bios (look at the bottom of the page for commands to say
how to exit, usually F10 key and Y for yes to save) and then turn off the
power. Pull out the power cord from the wall. Ground yourself to a radiator
momentarily to get rid of static electricity before opening the case.
If all this sounds scary and you have valuable data on your machine get
some personalized help rather than start poking around and trying this or
that. Your data is important,- right?