Roundcube
This project is a free and open source webmail solution with a desktop-like user interface which is easy to install/configure and that runs on a standard LAMPP server. The skins use the latest web standards such as XHTML and CSS 2. Roundcube includes other sophisticated open-source libraries such as PEAR, an IMAP library derived from IlohaMail the TinyMCE rich text editor, Googiespell library for spell checking or the WasHTML sanitizer by Frederic Motte.
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