Mail server

SMTP with TLS
POP3-IMAP4 with SSL
Webmail
Antispam
Antivirus
User quota support

LAMP server

Apache, MySQL, PHP, Perl and Python.

LDAP Directory server

Central management of users and groups
Master/slave architecture Windows Active Directory synchronization

File sharing

Windows file sharing (CIFS)
Primary Domain Controller (PDC)
Advanced password policies
Roaming profiles
Windows 7 support

Printer sharing

Printer management
Windows printer sharing

Backup

Incremental and full backup
Advanced backup policy
Disaster recovery

DHCP server

Dynamic and static leases