When you perform DNS monitoring tests on on a Windows 2000 non-domain controller, the MMC snap-in does NOT perform all the initializations that it does for a domain controller.
To workaround this issue:
1. If you have NOT installed the Adminpak.msi, do it now.
2. Open a CMD.EXE prompt and type MMC.EXE.
3. On the Console menu, use Add/Remove Snap-in to add the Active Directory Users and Computers snap-in.
4. On the Console menu, use Add/Remove Snap-in to add the DNS snap-in.
5. Expand the Active Directory Users and Computers snap-in, expand the domain tree and press any expanded item, such as Users. This initializes the routines required for the DNS snap-in to function.
6. In the Tree view, right-click the DNS snap-in and connect to the appropriate DNS server.
7. Right-click the DNS server and press Properties.
8. Use the Monitoring tab to run the tests.