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FreedomStack Component

Enterprise email and calendar.
Your infrastructure, your data.

Zimbra Collaboration Suite replaces Exchange Online with full Outlook compatibility, shared calendars, contacts, mobile sync, and enterprise anti-spam -- all self-hosted with zero per-user licensing.

Outlook Compatible ActiveSync Support Built-In Anti-Spam Self-Hosted
The Platform

Zimbra Collaboration Suite

Zimbra 10 is a mature, enterprise-grade email and collaboration platform used by over 200,000 organizations worldwide. It provides email, calendar, contacts, tasks, and briefcase (file sharing) in a modern web interface with full mobile device support.

Zimbra has been delivering enterprise email since 2005. The open-source edition includes everything most organizations need: IMAP/POP3/SMTP, a modern AJAX web client, ActiveSync for mobile devices, CalDAV/CardDAV for calendar and contact sync, shared calendars and mailboxes, distribution lists, resource booking, and built-in anti-spam and anti-virus filtering.

Unlike Exchange Online, Zimbra runs on your infrastructure. Email data never leaves your control. There are no per-user licensing fees, no storage caps, and no surprise price increases. Your 100-user organization gets the same features as a Fortune 500 company.

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Capabilities

Enterprise email without enterprise pricing

Full Email Suite

IMAP, POP3, SMTP with a modern web client. Conversations, tags, filters, search, signatures, vacation replies, and out-of-office. Everything you expect from enterprise email.

Shared Calendars

Free/busy lookup, meeting scheduling, resource booking for rooms and equipment, recurring events, and delegation. Syncs with Outlook, Apple Calendar, and mobile devices via CalDAV.

Mobile Sync

ActiveSync support pushes email, calendar, and contacts to iOS and Android. Remote wipe capability for lost devices. Works with Outlook mobile, Apple Mail, and native mail apps.

Anti-Spam & Security

SpamAssassin and ClamAV built in. SPF, DKIM, DMARC enforcement. TLS encryption for all connections. Optional S/MIME for end-to-end encrypted email.

Shared Mailboxes & Lists

Distribution lists, shared mailboxes with delegated access, send-on-behalf and send-as permissions. Manage everything from the Zimbra Admin Console.

Archiving & Compliance

Message archiving, legal hold, eDiscovery search, audit logging, and configurable retention policies. Meets HIPAA, SOC 2, and GDPR data residency requirements.

Side by Side

Zimbra vs Exchange Online

Email & Web Client

ZimbraModern AJAX web client, conversations, tags, search
ExchangeOutlook on the web (OWA), Focused Inbox

Outlook Support

ZimbraActiveSync, IMAP -- works with Outlook desktop & mobile
ExchangeNative MAPI, ActiveSync, full Outlook integration

Calendar & Scheduling

ZimbraShared calendars, free/busy, room booking, CalDAV
ExchangeShared calendars, scheduling assistant, room booking

Anti-Spam

ZimbraSpamAssassin + ClamAV + SPF/DKIM/DMARC
ExchangeExchange Online Protection (EOP) included

Data Location

ZimbraSelf-hosted, full data sovereignty, your encryption keys
ExchangeMicrosoft-hosted, US CLOUD Act applies

Cost (100 users/yr)

Zimbra$0 licensing + ~$1,800 hosting
Exchange Online$4,800/yr (Plan 1) or included in M365
FAQ

Common questions about Zimbra

Does Zimbra work with Outlook?

Yes. Zimbra supports ActiveSync and CalDAV/CardDAV, allowing Outlook on desktop and mobile to connect natively. Users can continue using Outlook as their email client with full email, calendar, and contacts synchronization. Zimbra also provides its own modern web client as an alternative.

How do you handle spam and phishing?

Zimbra includes built-in anti-spam (SpamAssassin) and anti-virus (ClamAV) filtering. We layer additional protections including SPF, DKIM, DMARC enforcement, greylisting, and optional advanced threat protection. Deliverability is managed with proper DNS records, IP warm-up, and reputation monitoring.

Can we migrate existing Exchange mailboxes?

Yes. Zimbra includes migration tools that support IMAP-based mailbox migration from Exchange Online and on-premises Exchange. We handle the full migration: mailbox data, calendars, contacts, and folder structures. Migration is performed in batches with MX record cutover at the end, minimizing disruption.

What about shared mailboxes and distribution lists?

Zimbra supports shared mailboxes, distribution lists, and delegated access (send-on-behalf, send-as). Administrators can manage these through the Zimbra Admin Console. Resource mailboxes for meeting rooms and equipment are also supported with auto-accept scheduling.

Is Zimbra suitable for HIPAA compliance?

Yes. Zimbra supports TLS encryption in transit, AES-256 encryption at rest, audit logging, legal hold, and eDiscovery search. Because data is self-hosted, you have full control over data residency, retention policies, and access controls. Combined with Wazuh for monitoring, the FreedomStack meets HIPAA, SOC 2, and GDPR requirements.

Own Your Email Infrastructure

Get your free cost assessment today

We'll analyze your current Exchange setup, map your mailbox migration, and show you what Zimbra looks like for your organization. No obligation.

Average response time: 4 hours
Call us directly(908) 868-1674
LocationSt. Petersburg, FL & Northern NJ
Response timeWe reply within 4 hours on business days