Next or Previous posts not working

Hi there,

I’ve a very valuable blog that has around 150 visitors a day. But I suddenly noticed that my link: <<PREVIOUS POST and NEXT POST>> aren’t working anymore!

Maybe the latest update of wordpress has caused that problem. Anyway, I’m using these tags in my template:

<div class=”navigation”>
<div class=”alignleft”><?php next_posts_link(‘« Previous Entries’) ?></div>
<div class=”alignright”><?php previous_posts_link(‘Next Entries »’) ?></div>
</div>

Please help, my visitors must be able to see all posts!