As far as I understand you are using the RadTreeView1_NodeExpand event handler in order to load the nodes on demand. In the attached sample project all nodes that are loaded on demand have ExpandMode
property set to TreeNodeExpandMode.ServerSideCallBack.
This means that all of them will have plus sign and will load nodes on demand if you click this sign. An easy and convenient way of avoiding this behavior is simply not to set ExpandMode
for your last node.
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