CAPTCHA

2. Download CAPTCHA 1.1 from the SquirrelMail site. If your version of SquirrelMail is not 1.5.2+ or 1.4.10+, download Compatibility 2.0.11.

3. Extract the downloaded files and put them into the /usr/share/squirrelmail/plugins directory

4. From a Terminal window, type in /usr/share/squirrelmail/config/conf.pl and press Enter. This will launch the SquirrelMail Configuration utility.

5. Type in 8 and press Enter to list the Plugins submenu. 

6. Install the captcha plugin by typing in the number corresponding to it and press Enter. When you are done, type in q and press Enter to quit then type in y and press Enter to save your changes

7. Install php-gd by typing in yum install php-gd. PHP-GD is required by almost all captcha backends.

8. In the /usr/share/squirrelmail/plugins/captcha directory, copy the file config.sample.php and save it as config.php. Edit config.php and assign a value to $captcha_backend.

9. If your version of SquirrelMail requires the compatibility plugin, go to /usr/share/squirrelmail/plugins/compatibility and apply the compatibility patch by typing in the command below. 

patch -p0 < patches/compatibility_patch-1.4.8.diff

Replace 1.4.8 with your SquirrelMail version.

10. Restart the httpd service. Learn how to start and stop services here.

11. Connect to your SquirrelMail server, you should see the CAPTCHA in your login page. 

If you encounter a blank page, check the log file at /var/log/httpd/error_log.