@GalacticGal Ah, okay. Glad you got it figured out, but bummer that tray file could be corrupted. That's not good to hear. I have a copy of every Sim/Lot tray file I've ever created, right from the beginning. I've put tray files previously taken out back in the game without any problems. But, they were all more recent files. I wonder what would happen if I tried to put an older file back in, say from 2014 or 2015. There's been a lot of patches since then and I have way more packs. Hopefully it wouldn't cause an issue, but hearing what happened to you makes me wonder.
Anyway, have a great rest of your weekend and Happy Simming! :)