Vibe SEO Pack is a simple powerful and easy to use SEO tool to optimize your website for search engines without having to edit a single line of code.
In this case your theme code is not written according to WordPress standards. To fix the problem go to your WordPress Dashboard - Appearance - Editor and select footer.php for editing. Now add this code:
<?php wp_footer(); ?> bellow the
</body> tag. Save changes and you're done. If your footer.php file contain encrypted code you should really think about changing your theme.