Have you tried creating an new project, if that doesnt work either something is broke with your unreal installation.
If creating a new project works, than you could copy everything from your old, broken, project over to the new one.
Have you tried creating an new project, if that doesnt work either something is broke with your unreal installation.
If creating a new project works, than you could copy everything from your old, broken, project over to the new one.