Welcome to the forum, just so you are aware this is a user to user forum so the responses that you will usually receive will be from other users like yourself. You need to supply info about the application you are using and the version number. In addition also info on the computer operating system and version number, you are using. Some more details of the problem you are experiencing.
Regards, Denis: System iMac mid-2015, 5K 27”, Ram 24GB, HDD 3TB, macOS 11.1, LrC 10.1 (>10.0), Lr 4.1, Ps 22.1, Pr 14.8.0; Camera OM-D E-M1.
I am using an apple Imac 2019, I updated my computer and now I am running the Catalina version.. before I updated the computer lightroom was crashing every time I open it.. and now its upgrade to the new version ( It did this by its self ) and then when I go to open it comes up with this... Lightroom classic catalogue upgrade.. so I hit upgrade and when it crashes again..