We try to inherit the "Microsoft.Web.UI.WebControls.TreeView" web control in order extend his functionality (I'm using C#).
We find a problem to add this control to any Aspx file , and we get the error code as you see in the attached file.
We try to do what suggested , but it seems that it doesn't help at all.
If anyone know on any problem regarding the one we have , please let us know.
Thanks
