You misunderstand what UploadFile does. It doesn't save the file to the target server, it simply POSTs the file to the url as if it had been a form submission;
<form action="upload.aspx">
<input type="file" name="myfile"/>
</form>
So the url you "upload" to has to be a page that can read the files posted to it and save them.
WebClient.UploadFile Method (String, String) (System.Net)[
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