The most serious problem with this device is that any kind of botched installation tends to be terminal - often requiring a complete reformat to fix it. I have had direct experience of this on several occasions.
You could try downloading the latest Snapscan software from the Agfa site - this includes drivers for 2000/XP. However note my previous point.
Follow the advice on the Agfa site to 'completely' remove the old software and drivers. Take the time to hunt down everything you can find. Then follow the installation instructions exactly. The process is not forgiving.