One of the following directory services
- GroupWise:
- Linux:
- eDirectory 9 plus the latest patch for Linux (recommended)
- eDirectory 8.8 plus the latest patch for Linux (supported)
- Windows:
- Microsoft Active Directory on Windows Server 2016 (recommended)
- eDirectory 9 with the latest patch for Windows (recommended)
- Microsoft Active Directory on Windows Server 2012 R2 (supported)
- Microsoft Active Directory on Windows Server 2012 (supported)
- Microsoft Active Directory on Windows Server 2008 R2 (supported)
- eDirectory 8.8 with the latest patch for Windows (supported)