Pagination for previous page/next page (with more than one post/page)

Try the following:

Reference: posts_nav_link

<div class="navigation">
<div class="alignleft"><?php previous_posts_link('&laquo; Previous Entries') ?></div>
<div class="alignright"><?php next_posts_link('Next Entries &raquo;','') ?></div>
</div>

Don’t use next_post_link or previous_post_link they are used for single post pagination.