Thumbnails in Categories

[Calleigh]

Hi guys..

I read the thread here about adding thumbnails in categories and it says I need to find this code from
my archieves.php

<?php the_excerpt(); ?><div class="clear"></div>

and I replaced it with this code:

[img]<?php echo get_post_meta($post->ID, [/img]" alt="<?php the_title(); ?>" />
<?php else: ?>
<?php endif; ?>


<?php the_excerpt();?><div style="clear:both;"></div>

But the problem is the thumbnails are not showing. custom fields from all my posts are set to thumb but still no thumbnails appearing when you click the categories.

Am i missing something here? Please help me to figure this out.. Thank you so much..