WebUpload first uploads the file into the ~/Uploads folder, during the uploading process file has a temporary name. After it is uploaded the temporary name is changed with the real file name. You could handle OnUploadFinishing event, then cancel this event, at this the file is uploaded but it is with the temporary name. Cancelling the event will prevent file renaming. Set the file name manually and move/copy it into the desired folder on the server.

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