Hello,
The "noscript" element is allowed in HTML5, but not in XHTML/XML documents.
If you need to use "noscript", then you should probably change your document type from one that is based on XML.
This talks a little more about it:
http://wiki.whatwg.org/wiki/HTML_vs._XHTMLIn XHTML, the element is always parsed as a normal element, and can't really be used to stop content from being present when script is disabled.