I did, in fact, have to reinstall Windows, go through the umpteen cycles of installing patches and service packs, and then reinstall all my software one piece at a time, despite having a full backup made a day earlier. Which is very frustrating. Windows is so dumb about some things.
Fortunately since this is just a server, there wasn't as much to reinstall as on most things. Once Windows was set up, I only had a few hours of services and configuration stuff to fiddle with, to get remote access (had to use VNC since XP Home doesn't serve as an RDP server), file shares, printer sharing, security, virus protection, and basic utilities working. After that, there are three major applications.
HomeSeer: This turned out to be a lot harder than it should have been. The existing files were not willing to run, but new installs also kept refusing to work with my existing configuration and data. It turned out I had to override the folder name it installed into to use the exact same folder name of my old install, then copy in only selected files and folders, which I had to pick out from hundreds of others, and which weren't obvious selections at all. Plus reinstall one USB device driver that the install claimed it had installed. But after a few hours, HomeSeer was back to where it was.
TVersity: The existing install wouldn't work here either, but reinstalling it was no great hardship as there's not a lot of configuration or data to rebuild. It did remember all of my library shares, but unfortunately, I was forced to change the media drive's drive letter so none of them worked. They were easily rebuild and rescanned, though. Took about 15 minutes of my time, and a few hours of library rebuilding, for it to be back to status quo.
PaperPort: My scanner is hooked to the server just because it's easier for me to operate remotely via VNC/RDP than to kick Siobhan off her computer. Unfortunately, I can't for the life of me find the CD that came with it, which had not just the drivers (I have those) but also the bundled scanner, document manager, OCR, and photo editor software. Naturally you can't download that either! (And the current version of the same thing costs more than the scanner originally cost me.) I've actually ended up reorganizing my entire software shelf (and Siobhan cleaned her desk!) but it hasn't turned up. If I can't find that, the scanner becomes a brick. This is very frustrating because I can see the disc in my mind's eye but I can't find it. There just aren't that many places I keep things like that! What's even more frustrating is that all the files I need are on my hard drive and/or backup, but I have no way to figure out which ones they are and get them installed to the satisfaction of the software.
Tomorrow, despite there being more technology news to report, I think I'll change the subject for a day just to break up the tedium.