Need more info than that.
What video card do you have?
What happens when you try to install driver?
Or you could try using the driver which came with the card, should be on a CD if you bought the card and it came with a driver. I know it won't be be the most up-to-date driver but you can update the driver once it's installed.
So you're using the CD the card came with? Just go to NVIDIA's site and download the latest one if so.
If it's only saying the installer is corrupt when you try to update and the driver on the CD worked for you, just use that.