This NIJ Special Report presents the results from testing the Writeblocker Windows 2000, Version 5.02.00 in accordance with the ACES Software Write Block Tool Specification & Test Plan Version 1.0. It documents results against three top-level tool requirements identified by the specification and several test assertions related to those requirements, describes the testing environment, provides an interpretation of the test results, and includes test results summary log files for numerous test cases. The results provide the information necessary for developers to improve tools, users to make informed choices, and the legal community and others to understand the tools' capabilities.