But reading your post I don't see what a login is needed here. Tell more.
I have an XP PC that is running Plex Media Server. Plex is great however if I don't reboot the PC every few days, it quits working. As soon as I reboot, it's fine again. I can live with this but I would like to schedule an auto-reboot every day at 3:00 AM. To complicate things, I have 4 user profiles set up on this XP machine so when it reboots I would like it to log into the user account that has the Plex Media Server. That user account is currently password protected, but if necessary I can remove that password. I want to keep the other profiles because each of them are set up for retro gaming and the PC is connected to my smart tv and I do occasionally log into these user profiles.