This is a good thought, Carlwhat - thank you for suggesting it. It brings something else to light. When I first installed Zen cart, I was running php 8.2.12. I got 500s on the zen cart pages. They went away when I bumped php down to 8.0.30. I just brought it back up to 8.2.12, and tried to hit the https://www.dans.com/zencart/ and the https://www.dans.com/zencart/zcadmin pages. I got the 500s again. Then I put php back to 8.0.30, and checked the log. I see a new entry for that invalid locale error that I don't understand again. So I think that's a php version issue - or something that needs to be fixed if I want to use 8.2.12 (and I do...). If I were to guess, I'd dare say this is a different problem, not the one causing the causing the loop of death.