First of all thank you Beanzvision, forgive me, I think I didn't understand or explained myself badly, my English is not the best.
I try to explain myself better, the render have been saved automatically, all in cxr format with the take set, the views to be rendered were 4, one has been completed and the other three seem almost to have not been completed also because the cxr file has a smaller dimension, so I believe that the editor is not the cause, but the problem is to be found elsewhere.
If it can be useful I will pass you one of these cxr files.