Hi,
I have the same problem . I'm using a page contains an Iframe which source is multiple-file-upload.aspx in demo source :
<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<table id = "tblabc">
<tr>
<td>
<iframe src="../
multiple-files-upload.aspx" height = "500" width = "500" style="padding-top:20px; margin-left:10px; margin-right:23px; padding-bottom:15px;"></iframe>
</td>
</tr>
</table>
<input type="button" value = "click me" title = "Show Upload" onclick = "document.getElementById('tblabc').style.display = 'block';" />
</form>
<script type="text/javascript">
document.getElementById("tblabc").style.display = "none";
</script>
</body>
</html>
I'm running this code in window XP, IE7, (Flash 9 or Flash 10).
I think this code cause the problem in flash: document.getElementById("tblabc").style.display = "none"; and make the upload file can not run.
(I'm running this code in many computers, and about half of them get this problem) .
Thanks.