SquirrelMail – webmail package written in PHP

SquirrelMail is a webmail package. It has all the functionality you would want from an email client, including strong MIME support, address books, and folder manipulation.

SquirrelMail outputs valid HTML 4.0 for its presentation, making it compatible with a majority of current web browsers. SquirrelMail uses a plugin architecture to accommodate additional features around the core application.

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.

It has very few requirements and is very easy to configure and install.

SquirrelMail is stable enough to use in a production system, and is very popular with educational organisations.

SquirrelMail allows you to log in to your IMAP and SMTP servers using plaintext, CRAM-MD5 or DIGEST-MD5, as well as use SSL for extra security.

Features include:

  • Composing, sending and receiving emails.
  • Supports HTML email, pure text.
  • Search function.
  • Mail filtering.
  • Folders.
  • Address books.
  • Calendars.
  • Threading.
  • Automatic forwarding.
  • Multiple mailboxes.
  • Supports IMAP (tested with Binc IMAP, Courier-IMAP, Cyrus IMAP, DBMail, Dovecot, MailServer, Mercury IMAP, and UW IMAP).
  • POP3 support.
  • Connect to an IMAP server via SSL.
  • Use the software in an intranet.
  • LDAP Address Book support.
  • Works with any Mail Transfer Agent via SMTP.
  • Extra features are available in the form of plugins:
    • Over 200 third-party plugins are available: Plugins for S/MIME and GPG/OpenPGP, Virtual Host, New Mail and many more.
  • Translated into over 40 languages.

Support: Documentation
Developer: Alex Lemaresquier, Alexandros Vellis, Chris Hilts, Fredrik Jervfors, Jonathan Angliss, Marc Groot Koerkamp, Paul Lesneiwski, Seth E. Randall, Steve Brown, Thijs Kinkhorst, and many contributors
License: GNU General Public License v2.0


SquirrelMail is written in PHP. Learn PHP with our recommended free books and free tutorials.

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