A file field cannot be given a value, this is a security issue implemented by the browser, it is not possible to have the file field retain the selected file, it will need to be reselected on validation failure.
Your friends over here at WebAssist! These Dreamweaver extensions will assist you in building unlimited, custom websites.
These out-of-the-box solutions provide you proven, tested applications that can be up and running now. Build a store, a gallery, or a web-based email solution.