Free
AfterLogic WebMail Lite .NET 5.0
Free and easy-to-use webmail script with AJAX interface. Supports POP3/IMAP accounts, SMTP, SSL. Users can check and send mail, use address book. Skins, non-English languages, UTF-8. MS SQL/MySQL/MS Access backends supported.
Free
AfterLogic WebMail Lite PHP 7.6.3
Open source PHP webmail front-end for your existing mail server. Fast and clean AJAX interface, IMAP/SMTP/SSL, LDAP, folders, rich-text editor, address book, web admin panel, UTF-8, non-English languages, MySQL, cPanel, Plesk and DirectAdmin support.
Trial
MailBee WebMail Lite ASP 4.0
MailBee WebMail Lite is ASP webmail application which supports AJAX and skins. Users can receive, view, manage, compose, and send email through web interface (POP3 and SMTP supported). Source code included.