Fehler beim einbinden mit Include

Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /users/pippfan/www/user/index.php:8) in /users/pippfan/www/user/navigation/user_oben_navi1.php on line 2 Warning: require(../config.inc.php) [function.require]: failed to open stream: No such file or directory in /users/pippfan/www/user/navigation/user_oben_navi1.php on line 4 Fatal error: require() [function.require]: Failed opening required '../config.inc.php' (include_path='.:/etc/php/lib') in /users/pippfan/www/user/navigation/user_oben_navi1.php on line 4

<?php
require("config.inc.php");
?>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
       "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<title><?php echo $titel; ?></title>
<style type="text/css">
  body {
    color: black; background-color: #87CEFA;
    font-size: 100.01%;
    font-family: Helvetica,Arial,sans-serif;
    margin: 0; padding: 1em 0;
    text-align: center;  /* Zentrierung im Internet Explorer */
  }

  div#Seite {
    text-align: left;    /* Seiteninhalt wieder links ausrichten */
    margin: 0 auto;      /* standardkonforme horizontale Zentrierung */
    width: 870px;
    padding: 0;
    background: #ffffff;
    border: 2px solid #3A5FCD:
  }

  h1 {
    font-size: 1.5em;
    margin: 0; padding: 0.3em;
    text-align: center;
    background: #fed url(../../../src/logo.gif) no-repeat 100% 45%;
    border-bottom: 1px solid silver;
  }
 
 
  p#Navititel {
    clear: both;
    font-size: 0.93em;
    margin: 0; padding: 0.5em;
    text-align: center;
    font-weight: bold;
    background-image: url(images/style/footer.gif);
  }

  p#Navititel2 {
    clear: both;
    font-size: 0.93em;
    margin: 0; padding: 0.5em;
    text-align: center;
    font-weight: bold;
    border-top: 1px solid #000000;
    background-image: url(images/style/footer.gif);
  }

  ul#Navigation {
    font-size: 0.83em;
    border: 1px solid #000000;
    float: left; width: 200px;
    margin: 0 0 1.2em; padding: 0;
  }
  ul#Navigation li {
    list-style: none;
    margin: 0; padding: 0.4em;
  }
  ul#Navigation a {
    display: block;
    padding: 0.0em;
    font-weight: bold;
  }
  ul#Navigation a:link {
    color: black; background-color: white;
  }
  ul#Navigation a:visited {
    color: #666; background-color: white;
  }
  ul#Navigation a:hover {
    color: black; background-color: #eee;
  }
  ul#Navigation a:active {
    color: white; background-color: gray;
  }

  div#Inhalt {
    margin: 0 0 1em 220px;
    padding: 0 1em;
  }
  * html div#Inhalt {
    height: 1em;  /* Workaround gegen den 3-Pixel-Bug des Internet Explorer bis Version 6 */
    margin-bottom: 0;
  }
  div#Inhalt h2 {
    font-size: 1.2em;
    margin: 0.2em 0;
    color: navy;
  }
  div#Inhalt p {
    font-size: 1em;
    margin: 1em 0;
  }

  p#header {
    clear: both;
    font-size: 0.83em;
    margin: 0; padding: 0.5em;
    text-align: center;
    background-image: url(images/style/header.gif);
    border-top: 1px solid silver;
    color: #FFFFFF;
  }

  p#footer {
    clear: both;
    font-size: 0.83em;
    margin: 0; padding: 0.5em;
    text-align: center;
    background-image: url(images/style/footer.gif);
    border-top: 1px solid silver;
  }
p#box {
background-color: #B0E2FF;
border-bottom: 1px solid #87CEFA;
border-right: 1px solid #87CEFA;
border-left: 1px solid #87CEFA;
position: absolute ;
width: 330px;
right: 200px; 
top: 2px
}
</style>
</head>
<body>
<div id="Seite">
<?php echo $logocode; ?>
  <p id="header">
<?php
    include "navigation/user_oben_navi1.php";
?>  
</p>

  <ul id="Navigation">
<?php
if(isset($_SESSION['UserID']))
    include "<?php echo $url; ?>/navigation/user_links_navi.php";
else
    include "<?php echo $titel; ?>/navigation/gaeste_links_navi.php";
?>  

  <div id="Inhalt">
llllljgouzi




</div>

  <p id="footer">
<?php
if(isset($_SESSION['UserID']))
    include "navigation/user_unten_navi1.php";
else
    include "navigation/gaeste_unten_navi1.php";
?>  
</p>
</div>


</body>
</html>

<p id="Navititel">Login</p> <li><a href="einfuehrung.htm">Downloads</a></li> <li><a href="mehrspaltige.htm">Tutorials</a></li> <li><a href="fixbereiche.htm">Fixe Bereiche mit CSS-basierten Layouts</a></li> <li><a href="navigationsleisten.htm">CSS-basierte Navigationsleisten</a></li> <li><a href="browserweichen.htm">CSS-Browserweichen</a></li> <p id="Navititel2">Webservice</p> <li><a href="einfuehrung.htm">Downloads</a></li> <li><a href="mehrspaltige.htm">Tutorials</a></li> <li><a href="fixbereiche.htm">Fixe Bereiche mit CSS-basierten Layouts</a></li> <li><a href="navigationsleisten.htm">CSS-basierte Navigationsleisten</a></li> <li><a href="browserweichen.htm">CSS-Browserweichen</a></li> </ul>