RadFileExplorer control is based on MS AJAX client-side framework and it needs that Framework to be fully loaded in order to use the RadFileExplorer's clint-side object. This is why you need to use the Load event
of the framework in order detect when its is fully loaded. Then you can find the RadFileExplorer control and call its methods.
In addition, I recommend you to cancel the ItemCommand event (e.Cancel = true). I recommend you this in order to avoid two simultaneous callbacks at the same time: the first one which is triggered when a file/folder is deleting and the second one which will occur when the oExplorer.refresh(); is called.
In case that the suggested does not help, could you please open a new support ticket and send me a runnable project which shows the problem? I will rework it in order to make it to work and send it back.
I hope this helps.
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