RadEditor for ASP.NET AJAX does not offer a built-in way to upload a file to a FTP server. To do that you should implement a custom file browser content provider and write the needed code in the StoreFile
function which is executed when a file is being uploaded.
As Dobromir wrote: There is an example of a FTP content provider which is available in the following KB article:
Connecting the RadFileExplorer to a FTP filesystem
My suggestion is to examine its code and customize it to achieve your scenario.
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