Cannot access as it keeps saying "Lightroom Catalogue v12 is corrupt " what is this?

[andrewr68761390]

Cannot access LRCC as it keeps saying that "Lightroom Catalogue v12 is corrupt" what is this? and how do I fix this issue?

[moved from bugs to discussions according to community policy - Mod.]

[F. McLion]

Start LrC while holding down the Alt key. This opens a dialog where you can start LrC with a new catalog, to verify LrC works as expected.

In addition, the dialog offers to check/repair the integrity of the faulty catalog. If that does not work, you will have to open and use the latest backup of your catalog.

[dj_paige]

Use a recent backup copy of your catalog file. You will have to unzip it before you can use it.