OpenLDAP for Windows
OpenLDAP is a free suite of client and server tools that implement the Lightweight Directory Access Protocol (LDAP) for Linux. We created OpenLDAP for Windows, a package that you can also use for free. It works out of the box so no additional software is needed.
The package is based on OpenLDAP 2.4.34 and includes most of the features available on Linux. The default backend is Berkeley DB with SSL support. OpenLDAP for Windows features complete Unicode support. The package has been tested on Windows Server 2003, Windows Server 2008, Windows Server 2012, Windows Vista, Windows 7 and Windows 8.
OpenLDAP for Windows is free for private and commercial use.
You can learn how to install the OpenLDAP for Windows from this article.