loop error for search and archive ?

on this archive page i want the posts to have different bottom lines. i tried this with this loop:

<?php
/**
 * @package WordPress
 * @subpackage Default_Theme
 */

get_header(); ?>

	<div id="content">

		<?php if (have_posts()) : ?>

 	  <?php $post = $posts[0]; // Hack. Set $post so that the_date() works. ?>
 	  <?php /* If this is a category archive */ if (is_category()) { ?>
		<br />
        <br />
        <h6>l'archive ‘<?php single_cat_title(); ?>’</h6>
 	  <?php /* If this is a tag archive */ } elseif( is_tag() ) { ?>
		<br />
        <br />
        <h6>mot-clef: ‘<?php single_tag_title(); ?>’</h6>

 	  <?php /* If this is a monthly archive */ } elseif (is_month()) { ?>
		<br />
        <br />
        <h6>l'archive de <?php the_time('F Y'); ?></h6>
 	  <?php /* If this is a yearly archive */ } elseif (is_year()) { ?>
		<h6>l'archive de <?php the_time('Y'); ?></h6>

 	  <?php /* If this is a paged archive */ } elseif (isset($_GET['paged']) && !empty($_GET['paged'])) { ?>
		<h6>archives</h6>
 	  <?php } ?>

		<div class="navigation">
			<div class="alignleft"><?php next_posts_link('&laquo; des articles plus vieux') ?></div>
			<div class="alignright"><?php previous_posts_link('des articles plus recents &raquo;') ?></div>
		</div>

		<?php while (have_posts()) : the_post(); ?>

                <div class="post">
                  <div class="title-after"><h3><a href="<?php the_permalink() ?>"><?php the_title(); ?></a></h3></div>

                        <div class="post-content">
                        <?php the_excerpt(); ?>

                        </div> <!-- post content -->

<?php
    // articles with a certain category get a certain footer:
    if (is_category('actualites') || is_category('films') || is_category('ressources') )
    {
    ?>

<div class="post-after">
<small><b>:: </b><b><?php the_category(' ', ', ', ' '); ?>  <?php the_time('d/m/Y') ?></b> [ <?php edit_post_link(__('EDIT') ); ?> ] <?php comments_popup_link('Sans Commentaires »', '1 Commentaire »', '% Commentaires »'); ?>  </small>
</div> 

 <?php
    } else {
    ?>  

<div class="post-after">
<small><?php edit_post_link(__('EDIT') ); ?></small>
</div> 

<?php
    }
    ?>

<hr/>
              </div> <!-- post -->

		<?php endwhile; ?>

		<div class="navigation">
			<div class="alignleft"><?php next_posts_link('&laquo; des articles plus vieux') ?></div>
			<div class="alignright"><?php previous_posts_link('des articles plus recents &raquo;') ?></div>
		</div>
	<?php else :

		if ( is_category() ) { // If this is a category archive
			printf("<h2 class='center'>Sorry, but there aren't any posts in the %s category yet.</h2>", single_cat_title('',false));
		} else if ( is_date() ) { // If this is a date archive
			echo("<h2>Sorry, but there aren't any posts with this date.</h2>");
		} else if ( is_author() ) { // If this is a category archive
			$userdata = get_userdatabylogin(get_query_var('author_name'));
			printf("<h2 class='center'>Introuvable ... </h2>", $userdata->display_name);
		} else {
			echo("<h2 class='center'>No posts found.</h2>");
		}
		get_search_form();

	endif;?>

    </div> <!-- content -->  

<?php get_footer(); ?>

but somehow it’s not working … only the second bottom line is used 🙁
any idea why ? having same problem on search results …