public static void DeleteDropboxImage(DropboxInfo dropBoxInfo)
        {
            // Make sure we remove it from the history, if no error occured
            config.runtimeDropboxHistory.Remove(dropBoxInfo.ID);
            config.DropboxUploadHistory.Remove(dropBoxInfo.ID);

            // get the config of dropbox
            Dropbox.DropBoxConfiguration dropBoxConfig =
            CloudStorage.GetCloudConfigurationEasy(nSupportedCloudConfigurations.DropBox) as
            Dropbox.DropBoxConfiguration;

            // instanciate the cloudstorage manager
            CloudStorage storage = new CloudStorage();

            // open the connection to the storage
            storage.Open(dropBoxConfig, config.DropboxAccessToken);

            // get the root entry of the cloud storage
            ICloudDirectoryEntry root = storage.GetRoot();

            // delete a file
            ICloudFileSystemEntry fileSystemEntry = storage.GetFileSystemObject(dropBoxInfo.ID, root);
            if (fileSystemEntry != null)
            {
                storage.DeleteFileSystemEntry(fileSystemEntry);
            }
            // close the cloud storage connection
            if (storage.IsOpened)
            {
                storage.Close();
            }

            dropBoxInfo.Image = null;
        }