Catalog upgrade removes photos from catalog

[JonasGr]

This has happened to me twice now: After upgrading my Lightroom catalog, about the last year of photos have been removed from the lightroom catalog. Luckily, I regularly backup my catalog, so I could simply import the backup. However, why does this happen, and what can be done about it?

[JohanElzenga]

Most likely Lightroom opened and upgraded an older catalog rather than the current one.

[Theresa J · Accepted solution]

Lightroom will not remove photos. This only happens when you have opened a different catalog. Check your preferences and note the name and location of your current catalog. Next time you do an upgrade, make sure you are upgrading the correct one. You may want to find and remove the older catalogs that you don't need so this won't happen again.