it isn't their fault.
Does the scanner have a brand name? If it does you should be able to download some software for it. I'm not holding out too much hope on this, as I seem to remember we had a similar problem a long time ago, and it was a bit of a nightmare tracking down the scanner driver.
Does the scanner show up in device manager by the way? If it does, you can try the 'update driver' option, and get Windows to scan itself for the missing driver. Unless you deleted it you may get success with that method.