Basically the files in the Temporary Folder are supposed to be used only by the internal functionality of RadAsyncUpload and we do not recommended using them. Here is one way to get the file names of the already uploaded files in the target folder:
sender, FileUploadedEventArgs e)
targetFolder = Server.MapPath(RadAsyncUpload1.TargetFolder);
fileName = e.File.GetName();
+ targetFolder + fileName);
Hope this will be helpful.
the Telerik team
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