How to set value when use <input name="File1" type="File" value="?"

Hi, I'm trying to create a page to upload files automatically. This is my code:

<form name="frmUpload" action="upload.asp" method="post" enctype="multipart/form-data">
<input type="file" name="file1" value="<%=FilePath%>">
</form>
<script language="Javascript">
document.frmUpload.submit();
</script>

The problem is:
the "value" property is read only, the value couldn't be set unless user click "Browse" button and choose a file. Is there any way can change the value by coding. Thanks

Only with trusted script in Netscape (4+) - not at all in MSIE. If you could, you could remotely select a user's files and upload them programmatically - so much for privacy.