Do you use AJAX for updating the RadGrid and uploading the selected files? One of the known limitation of the RadUpload control is that it cannot upload files using AJAX calls and if you try to upload files with AJAX calls the UploadedFiles
collection will be empty. You can find more details about the problem and some workarounds in this help article
. For your convenience I have also attached an example demonstrating how to use RadUpload in an Ajaxified Grid.
Please, let us know if you need further assistance.
the Telerik team