There was a problem retrieving the XML data: Internal Server Error (Error 500)

I installed the FileVistaControl on my page for testing.
Most of it works fine: upload files, delete files, create folders, download files, ...

However, I can NOT delete a folder.  When deleting the folder, I receive the error "There was a problem retrieving the XML data: Internal Server Error (Error 500)".  What can be the problem.

On my test server, access is set to "Full control" for "Everybody".  So, it can not be an access rights problem.

Are you using a root folder within your project folder?
There is a feature of ASP.NET such that whenever a subfolder within the application's root folder is deleted the application domain is recycled. Thus you are getting the HTTP 500 error.

So you should use root folders outside the application folder. For instance, if your application folder is /FileVista, you should not use a subfolder like /FileVista/Subfolder as a root folder.