I had an issue come up when I tried to get into Lightroom today. It kept telling me I needed to use a different catalogue. I attempted to upgrade to a new catalogue and then lost all my files for 2018. I obviously did something wrong.
Now when I go into Lightroom - it's all as it was months ago and lots of files/photos from 2016 and 2017 that I deleted - are all back and all my files/photos for 2018 are gone!
I'm panicking, as I've lost all my clients images.!
I've tried to sort this out but nothing is working.
How do I re-install my latest catalogue?
What is shown when you open LR and go File > Open Recent ?
If Lightroom kept telling you that you needed to use a different catalog, then that dialog probably also said why. I assume it said that the catalog was corrupt, but we can’t be sure if you don’t tell us. If the catalog was indeed corrupted, then hopefully you made regular backups.
It sounds as if you now opened a very old catalog, possibly from last year. You should check for something more recent, so the first question is: do you make regular backups of your hard disk and/or did you let Lightroom make catalog backup on quit?