Hi LiamPowell,
Please try the example below on your site, then show me the full error message.
<%@ Page Language="VB" %>
<%@ Register Namespace="CuteWebUI" Assembly="CuteWebUI.AjaxUploader" TagPrefix="CuteWebUI" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs)
uploader1.SetAdvancedOption(UploaderAdvancedOption.NoFlash, "true")
End Sub
</script>
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title>Untitled Page</title>
</head>
<body>
<form id="form1" runat="server">
<div>
<CuteWebUI:UploadAttachments ID="uploader1" runat="server">
</CuteWebUI:UploadAttachments>
</div>
</form>
</body>
</html>
Regards,
Ken