ActiveXperts Network Monitor 2015 proactively manages network servers, devices, databases and more.

Microsoft Resource Kits - Windows 2003 Resource Kit

Usrmgr.exe  (Windows 2003 Resource Kit)

The Window Server 2003 Resource Kit is a set of tools that system administrators and engineers use to manage or support a Windows Server 2003 system. Use it to streamline management tasks such as troubleshooting operating system issues, managing Active Directory, configuring networking and security features, and automating application deployment.
Usrmgr.exe - User Manager for Domains
Use this GUI-based tool to manage security for Microsoft® Windows® 2000 Professional and Microsoft® Windows NT® version 4.0 domains, member servers, and computers. It enables you to manage a Windows NT 4.0 domain from a Windows 2000 computer.