The default content provider, that ships with the editor and file explorer controls will only work with files in the current web application. Naturally, there are scenarios where you wish to show files that are not physically in the application folder. The provider model allows you to do just that - you can either customize the existing provider (FileSystemContentProvider) or write a completely new one (FileBrowserContentProvider).
We recently went through the forums and noted what custom providers are most frequently used with the RadEditor and RadFileExplorer controls. After that we created sample providers for those scenarios and posted them as support resources so people don't have to write them from scratch. Here are the links to those resources:
We hope that these will be useful and will save you some development time. For more information about the content provider model, see the following link - Using a custom FileBrowserContentProvider