I have installed Windows 10 and the last version of Kicad (5.1.5)-3
The problem Kicad sch freeze and dond’t recognise my old version of project (sch and pcb ) made with with an old version of Kicad.
S.0.S pleause help me 
@Djoss, do you remember what version of Kicad you last used on your older projects?
If this is really an issue with Kicad 5.1.5-3 and Windows 10, I would really recommend you post this issue on Kicad’s Forum. That way the developers of Kicad can become aware of the of the issue and can help you fix it.
Regards,