Weird sky sphere problem

Hi,

I’ve a problem with every project I open, my sky sphere looks like “uncalculated”. It works perfectly on others computer but I can’t find which parameter goes wrong on this pc. Thank you for help (sorry for bad english), have a nice day.

If I place a new one nothings change, but when I remove it completly the sky looks functionning and in content browser if I open the sky sphere BP, it looks broken by default.