OpenChange
OpenChange is an open source implementation of Microsoft Exchange Server that allows Linux and UNIX servers to interoperate with Microsoft Exchange clients. It provides compatibility with Exchange protocols like MAPI, EMS, and OAB.
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OpenChange: Open Source Implementation of Microsoft Exchange
OpenChange is an open source implementation of Microsoft Exchange Server that allows Linux and UNIX servers to interoperate with Microsoft Exchange clients, providing compatibility with Exchange protocols like MAPI, EMS, and OAB.
What is OpenChange?
OpenChange is an open source server software that aims to provide seamless compatibility with Microsoft Exchange servers and clients. Developed by Julien Kerihuel, OpenChange allows organizations to operate Linux-based mail and groupware servers while supporting Outlook clients and other Microsoft collaboration tools.
At its core, OpenChange attempts to fully mimic the functionality and behavior of Exchange Server through reverse-engineering Exchange protocols like MAPI, EMS, LDAP, OAB, and more. This allows OpenChange servers to connect with Outlook clients and provide access to email, calendars, contacts, tasks, and other collaboration features.
Some key capabilities and components of OpenChange include:
- Message store for preserving emails, appointments, contacts, tasks, and notes
- Compatible with Exchange mailbox protocols like MAPI and EMS
- Offers offline address book (OAB) support
- Public folder hierarchy replication
- Outlook Web Access (OWA) web interface
- Groupware functionality like shared calendars and global address lists
- Compatible with Outlook 2000 or newer versions
By providing a drop-in Exchange replacement based on open standards, OpenChange allows organizations to avoid vendor lock-in and have more control over their messaging and collaboration systems. The project is released under the GPL license.
OpenChange Features
Features
- Provides Exchange Server protocol compatibility on Linux
- Supports MAPI, EMS, OAB, and other Exchange protocols
- Allows Exchange clients to connect to Linux/UNIX servers
- Implements Exchange Server features like mailboxes, address books, calendaring
- Open source under the GNU General Public License v3
Pricing
- Open Source
Pros
Free and open source
Avoids licensing costs of Exchange Server
Enables Exchange compatibility on Linux/UNIX
Active development community
Cons
Limited feature set compared to full Exchange Server
Lacks some management capabilities
Interoperability issues with some Exchange clients
Limited enterprise deployment support
Official Links
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