I am using the latest released version of the control. In Page_Load I have the following code:
RadFileExplorer1.TreeView.EnableDragAndDrop = true;
RadFileExplorer1.Grid.ClientSettings.AllowRowsDragDrop = true;
It fails on the second line because the .Grid property is null at that point? If I don't have that code the program seems to run fine.
For reference, I added the above code to the bottom of Page_Load in the program "PhysicalPathFileSystemProvider_Cs.zip"
located at the bottom of the page on http://www.telerik.com/support/kb/details/use-radfileexplorer-with-physical-and-shared-folder-s-paths