Since I am not able to reproduce the described issue, I have attached a sample project that follows your instructions. The label tag purpose is to print the selected node text value when user clicks on the button when a node is already selected. Please note that the selected node is retrieved using the following expression:
Label1.Text = RadTreeView1.SelectedNodes.Text;
Please try to modify the attached project in order to replicate the described issue. This way we will be able to inspect it locally and assist you any further.
Looking forward to your reply.
the Telerik team
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