Lost GBs on my hard drive

[Vardon]

I tried to restore my computer system to correct a problem I was having and the tech  that I was talking to had me try to load the restore discs that came with my computer. That didn't work and I lost the operating system in my computer and had to load the operating system disc that came with my computer to get it to work again.  Well originally I had 40 gb on my hard drive. Now I only have 16.

When I follow this path: Start>Control Panel>Admin. Tools> Computer management> Disk Management I find on the hard drive I have 16.1 gb being used and 21.24 gb are unallocated.

How do I get all of the original Hard drive Back??

[Spoiler]

Any of the CDs you have say something like drivers? It sounds like you need to load the drivers for your machine....

[BC_Programmer]

if it's vista, you can resize your drive; but otherwise you might have to settle with the creation of a data drive from your unallocated space.

[Vardon]

I have only 1 operating system disc and 4 restore discs that wipe out everything On my hard drive.