These are the steps that you need to follow. There are quite a number of steps because v2.2 is a few years old. It would be best to practice this on a staging site first.
1. Download version 2.5.
2. Put the script in maintenance mode (Settings -> Maintenance).
3. Back up your database (Tools -> Database Backup) and your files.
4. In the v2.5 download, do the following:
- rename the /upload/ folder to match your /comments/ folder.
- rename the admin folder /upload/admin/ to match your admin folder.
- delete all the text files in /upload/includes/words/
5. On your server delete the folder /upload/includes/emails/
6. On your server delete the file /upload/includes/db/details.php
7. Upload the /upload/ folder onto your existing /comments/ folder to overwrite everything.
8. Run the upgrade
http://www.domain.com/upload/installer/
9. Log in to your admin panel and make sure everything is working.
10. Add your email signature in Settings -> Email -> Setup.
11. Take the script out of maintenance mode (Settings -> Maintenance).
12. In the pages where Commentics is integrated, do the following:
- remove the line: ob_start();
- remove the line: <link rel="stylesheet" type="text/css" href="comments/css/stylesheet.css"/>
- remove the line: define('IN_COMMENTICS', 'true'); //no need to edit this line
