Hi Didier, We haven't had a chance to test IDL 8.5 on Windows 10 yet, but most of the time installing older software works on newer versions of Windows. I would imagine there is going to be a property that lets you run a program in compatibility mode for Windows 7 or Windows 8, just as there has been on other versions of Windows. Another important thing to point out is that IDL 8.5 is officially supported for Windows 10 and is now available for download. You can view your available downloads through the Downloads link of My Account on our web page