Our suggestion is to check the permissions of the folder by following the instruction described in the following help article: Troubleshooting
(An error like "... because the application did not have enough permissions..." occurs only in a production environment. How to debug the issue? ).
We have an article in our Knowledge Base that shows how to load shared folders in RadFileExplorer - it might be helpful for your scenario. Here is a link: Use RadFileExplorer with physical and shared folder's paths
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