If you want to load your images from the root directory of your application, you wil want to set the grid.DisplayLayout.Images.ImageDirectory to ~/
The '~' will tell the control to navigate to the root directory. You could also makes use of other symbols such as '..' for the parent folder depending on your needs.
In addition to this option you also can also use a web.config redirect to tell all Infragistics controls to look for the images in a specific folder. In this scenario you can make use of the '~' as well. Here is a Knowledge Base article that explains how you could modify the web.config:
http://devcenter.infragistics.com/Support/KnowledgeBaseArticle.aspx?ArticleID=6158
No no ...
I don't need any work around like ~,.. or other
Here is the quiestion - Can I or can't set the ImageDirecty property to empty string?