SquirrelMail is a web based email (webmail) client. It includes built-in pure PHP support for the IMAP and SMTP protocols, and all pages render in pure HTML 4.0 (with no JavaScript required) for maximum compatibility across browsers. SquirrelMail is Open Source.
SquirrelMail webmail uses a plugin architecture to accommodate additional features around the core application, and over 200 plugins are available on the SquirrelMail website. SquirrelMail has all the functionality of a desktop email client, including strong MIME support, address books, and folder manipulation, all in a web based email platform.
Install SquirrelMail
Postfix, Dovecot and SquirrelMail in CentOS/RHEL/Scientific Linux 6.3
Redhat, Fedora, CentOS
Install the EPEL Repository to install SquirrelMail package.
Follow the instructions in: EPEL Repository
Now install squirrelmail
yum install squirrelmail
Depending on how you structured your Apache2 html documents, and where your document root is, you may have to move stuff around. The default install path for SquirrelMail is
/usr/share/squirrelmail
With some configurations files in
/etc/squirrelmail httpd/conf.d/squirrelmail.conf cron.daily/squirrelmail.cron