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Microsoft Resource Kits - Windows 2000 Resource Kit

Freedisk.exe  (Windows 2000 Resource Kit)

The Windows 2000 Resource Kits help IT professionals deploy, manage, and support Windows 2000 operating systems.
There are a number of Windows 2000 Resource Kit software tools available for free download from Microsoft. These tools are listed below, and can help you streamline administrative tasks such as managing Active Directory™, administering security features, working with Group Policy and Terminal Services, automating application deployment, and other important jobs.

Freedisk.exe
This command-line tool checks for free disk space. When it is used in a batch file, it returns a "0" if there is enough space and a "1" if there isn't. When used from the command line, FreeDisk returns "OK" when the disk space is available, and "Too Small" when it isn't.