If anybody is interested, this has been solved. The problem was that one TreeView's NodeClick event instantiated a form with TreeViews on it. The TreeViews on this child form did not fire. It seems you cannot fire a TreeView from within a TreeView!!
>Has anybody had any problems with the treeview events not firing?
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>Does anybody know of any issues relating to the treeview control?
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>Does anybody know of any alternatives?
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>We are using MSComCtrl.Treeview.2 and the NodeCheck event is not firing. This was working on some machines but now works on none.