CodeIgniter User Guide
Author: ExpressionEngine Dev Team

# CodeIgniter User Guide Version 2.2.1

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# Upgrading from 1.5.2 to 1.5.3

Before performing an update you should take your site offline by replacing the index.php file with a static one.

## Step 1: Update your CodeIgniter files

Replace these files and directories in your "system" folder with the new versions:

- system/database/drivers
- system/helpers
- system/libraries/Input.php
- system/libraries/Loader.php
- system/libraries/Profiler.php
- system/libraries/Table.php

Note: If you have any custom developed files in these folders please make copies of them first.

## Step 2: Update your user guide

Please also replace your local copy of the user guide with the new version.