“Sometimes when a user logs in, they get an empty desktop without their usual icons. When they log off and log back in, they get their expected desktop back. Why is that?”
This is a problem that I’ve experienced myself. As your system was coming up, something about the profile was seen to be corrupt, or otherwise unusable, and so the operating system gives you a temporary profile instead. (Your user should have seen a message that scared them about something being corrupted. I know it scared me.)
Here’s how it was explained to me:
“99 times out of 100 it is because an update needed to do some post reboot operation and it needed to be done by a full admin. The other time it is because something was holding the profile open during the login, and it was a glitch.”
So.. it’s quite annoying, and a little scary. But usually it’s not really serious. It really shouldn’t be happening often.. But if it is, you might want to consider perhaps that you have a failing hard disk or some other type of software or hardware corruption that is confusing things.