I have C# MVVM WPF project with using Telerik. All my "Views" inherits Telerik RadWindow. It works perfect when i use it in Windows 10. But when i run my application on windows 7 problems with displaying of icons appear. Maximize,minimize and many others icons display like rectangles. There are not any errors. I have no idea what could be the matter. I am a newbie in this field. I attached screenshot with my problem.