zFTPServer is a multi threaded Windows FTP server. Although being extremely simple to use, there exists an advanced configurations mode which should satisfy every need. Also, extensions are available that makes this into a full-fledged Integration Server with the following highlights:

Protocols: FTP, FTPS, SFTP, TFTP, HTTPS
Virtual filesystem: Possible to mount any disk drive or directories at anywhere within the home directory of a user or group. This makes it possible to for instance merge several directories so they seem as one.
SSL/TLS support: Strong encryption support (up to 256 bits AES).
Automatic updates: The server will update automatically when a new version is available (optional).
Scripting friendly: The server can be controlled through a standard TCP/IP connection, making scripts very easy to develop (e.g. creating new accounts through php).
Remote administration: The server and graphical user interface is separated which easily enables remote maintenance of the server.
Being a system service: Built in Windows 2000 / XP / 2003 / 2008 service support.
Ultrafast transfer speed: More than 11MByte/sec. average on 100MBit LAN, outperformes most of the "famous" windows ftp servers.
Passive mode host / ip option: Ability to specify a host name for a server with dynamic ip adress to use in passive mode, e.g. myserver.no-ip.com
Powerful user and group account management: Users and Groups may join multiple number of groups simultaneously.
Support for upload balancing: With the virtual filesystem users' uploads may end up where there is space.
Advanced IP-Access management: Access rights with respect to ip adresses or domain names may be specified, granting or denying access from specific locations.
Advanced Account expiration: Accounts can be expired after a specific criteria has been fullfilled. Criterias include expiration after a specific date, after a specified number of days/weeks/months has passed, number of downloads performed and more.

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