If your driver download is just a set of files and not an executable installer, you can manually add the printer via Windows settings:
Download from Seagull Scientific’s site or contact your distributor. Also, check archive.org’s Wayback Machine for older driver versions. wep th400 printer drivers download
Visit the WeP Solutions Support page. Navigate to the "Downloads" or "Drivers" section and search for "TH 400". If your driver download is just a set