The paths are configured properly in the provided code snippet, but could you confirm that you are setting them in the Page_Load event (or earlier)? This is the latest moment of the page life cycle in which you can configure RadFileExplorer, and if you are doing it in a later event, that could cause the issue. If this is not the case, could you prepare a sample fully runnable project reproducing the issue so we will be able to examine and debug it locally?
Regarding the disable-buttons issue - it turn out to be a known issue in RadToolbar (which is a child control fro FileExplorer) and we will do our best to fix it for one of our up-coming releases.
All the best,
the Telerik team
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