Zimbra Desktop is free e-mail and calendar software that runs on any Linux, Mac or Windows computer. The tool offers e-mail, contacts, calendar and document capabilities all in one application, and it lets users read e-mail from any POP or IMAP e-mail account, including Gmail, Hotmail or business e-mail. Owned by VMware, Zimbra works both online and off, and there's no limit to the size of your e-mail storage. As an added bonus, it's also available in 20 languages.
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