That did, indeed, fix the problem. I can boot into other DEs now. I don't
remember what message popped up just before the problem started. I was booting
and some error message popped up, and I clicked OK to continue because I had
something to do on the puter, and I figured if it causes a problem, I'll unwind
it later. The boot after that one was when the ICEauthority error started
happening.

I'm trying to get ahead of the curve here with the new DE replacing GNOME with
the next version. I know I've been told which it is, but I don't remember. Which
DE is replacing GNOME?