Did you restart your computer after installing the driver (sometimes needed)?
Do you have another cable you could try? If not, might check it with your meter.
Is it a USB or RS232. Guessing USB, if your PC is more than 5-6 years old, the USB might not be the same. Check that driver page and see if they have more than one for your camera. Also, that was the manufactuer's site, should be some E-mail support or FAQ, might help.