Roundcube Webmail for Windows

Roundcube Webmail, a browser-based multilingual IMAP server with an app-like interface, is available. It offers all the functionality you would expect from an email client including MIME support and message searching, address book manipulation, folder manipulation and spell checking.

These are the key features

Multilingual capabilities.Find-as-you-type address book.Richtext/HTML message composing.Searching messages and contacts.Canned response templatesNew.Int. Domain names (IDNA). Shared folders and ACL. Full featured address book. Extensible with the Plug-in API.

Roundcube Webmail is both free and inexpensive, so it could be a great solution for SMBs that want to offer webmail as a primary or second service.