Probleme d'arobase

Bonjour,

Je ne comprend pas pourquoi sur cette page l'arobase ne marche pas alors que sur les autre il marche.

Sorry, I am unable to validate this document because on line 99 it contained one or more bytes that I cannot interpret as utf-8 (in other words, the bytes found are not valid values in the specified Character Encoding). Please check both the content of the file and the character encoding indication.

The error was: utf8 "\xA9" does not map to Unicode

<div class="footer_legal_notice">
<a href="http://www.test.com"
target="_blank">© test</a> </div>
</table>
</body>
</html>

Merci d'avance pour votre aide.