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  <div class="section" id="upgrading-from-1-7-1-to-1-7-2">
<h1>Upgrading from 1.7.1 to 1.7.2<a class="headerlink" href="#upgrading-from-1-7-1-to-1-7-2" title="Permalink to this headline">¶</a></h1>
<p>Before performing an update you should take your site offline by
replacing the index.php file with a static one.</p>
<div class="section" id="step-1-update-your-codeigniter-files">
<h2>Step 1: Update your CodeIgniter files<a class="headerlink" href="#step-1-update-your-codeigniter-files" title="Permalink to this headline">¶</a></h2>
<p>Replace these files and directories in your &#8220;system&#8221; folder with the new
versions:</p>
<ul class="simple">
<li>system/codeigniter</li>
<li>system/database</li>
<li>system/helpers</li>
<li>system/language</li>
<li>system/libraries</li>
<li>index.php</li>
</ul>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">If you have any custom developed files in these folders please
make copies of them first.</p>
</div>
</div>
<div class="section" id="step-2-remove-header-from-404-error-template">
<h2>Step 2: Remove header() from 404 error template<a class="headerlink" href="#step-2-remove-header-from-404-error-template" title="Permalink to this headline">¶</a></h2>
<p>If you are using header() in your 404 error template, such as the case
with the default error_404.php template shown below, remove that line
of code.</p>
<div class="highlight-ci"><div class="highlight"><pre><span></span><span class="o">&lt;?</span><span class="nx">php</span> <span class="nb">header</span><span class="p">(</span><span class="s2">&quot;HTTP/1.1 404 Not Found&quot;</span><span class="p">);</span> <span class="cp">?&gt;</span>
</pre></div>
</div>
<p>404 status headers are now properly handled in the show_404() method
itself.</p>
</div>
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<h2>Step 3: Confirm your system_path<a class="headerlink" href="#step-3-confirm-your-system-path" title="Permalink to this headline">¶</a></h2>
<p>In your updated index.php file, confirm that the $system_path variable
is set to your application&#8217;s system folder.</p>
</div>
<div class="section" id="step-4-update-your-user-guide">
<h2>Step 4: Update your user guide<a class="headerlink" href="#step-4-update-your-user-guide" title="Permalink to this headline">¶</a></h2>
<p>Please replace your local copy of the user guide with the new version,
including the image files.</p>
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