All of my projects have gone missing from my Unreal libary

Hello,
Any help would be greatly appreciated. I am currently game art student and all of my Unreal projects have disappeared one day after working on a level all day. I could not figure out why this would happen so I just tried to load my back up files. And Unreal just wont open it. It opens then closes itself. I don’t know what to do or why this happened. I am on MAC if that is helpful piece of information. I am at a complete loss for what to do. Please any help would be appreciated.

Did you edit in UE5, and then go back to 4.26?

Just because you can’t find the projects in the Unreal Engine library doesn’t necessarily mean you can’t open them.

Have you tried opening the .uproject file for your project from your file manager?

Thank you so much for you response. No I didnt use UE5 for anthting yet. I have stayed on UE4 26.2 for my recent projects. And when I try to open the .uproject Unreal opens then closes itself a moment later