CS6 is not completely compatible to El Capitan.
BUt how did you install your InDesign? From the original installer? Or via migration from Backup or other computer? Only installing from original installer will work with InDesign programs.
Did you try to delete preferences?
Damn, I probably will have to install my InDesign from original installer…
Could you tell me how to delete preferences, please ?
Thanks a lot for your reply.
Thanks a lot for your advice. I think I'll try this solution.