Free
Zimbra Collaboration Server (ZCS) is sold per user mailbox in bundled packs of 25, 250 and 2,500. Packs are available as annual, multi-year and perpetual software licenses. Open Source Edition Zimbra Open Source Edition is a free email and collaboration solution ideal for individuals or smaller organizations that do not require Zimbra Support, advanced administration, business continuity and only IMAP email on desktops and devices. Special discounts are available for government, education and non-profit organizations.
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