I have a UMAX Astra 1220s which uses the SCSI interface. I am using Windows XP Pro. I have managed to find and install vs375u.exe and vs375u_382upd.exe, but I could not find xpupdater.exe . At this time vista32.exe could not find the scanner. The new hardware is detected, but I am not finding the SCSI Controller driver. I get a yellow question mark next to the SCSI Controller in Device Manager.
Solution: look up the FCC ID from the card in google: KQ53191D-1. I found the Domex drivers page: http://www.domex.com.tw/support/driver/d_3191d.htm
I downloaded and installed w2k.zip which is for win 2000. It warns that this is not XP tested, but I took the risk.
With the scanner ON, I rebooted, and then the scanner works.