This guide explains how to install the RoundCube webmail application on a Debian Wheezy server running ISPConfig and Apache2, and how to enable the ISPConfig 3 plugins for RoundCube so that users can perform actions like changing their email passwords from within RoundCube. Roundcube webmail is a browser-based multilingual IMAP client with an application-like user interface; it comes with functions like MIME support, address book, folder manipulation, message searching and spell checking.