Hi YvesRossignol
I'm not with Laminar Research, just a fellow simmer from the UK.
If I understand your question correctly, it seems as though your copy of XP11 'crashes' back to desktop (CTD) during the initial loading process?
Please could you therefore upload your XP11 Log.txt file to this post, so that I and others with a broader knowledge base, can review in an attempt to identify what is causing this problem?
If you not sure how to upload a file to this post, please click on the following link to view the PowerPoint slides that I have prepared for this specific purpose:- http://questions.x-plane.com/?qa=blob&qa_blobid=2316259919488063445
Regards