Health Checker is a Microsoft script used to review Exchange Server configuration and compare it against expected safe settings. Administrators run it after updates or maintenance to confirm that the server is still in a supported, healthy state and that required components are configured correctly.
In cyber security, this matters because an Exchange server can look patched while still being misconfigured, missing prerequisites, or drifting into an unsafe state. Health Checker helps defenders catch issues such as outdated versions, unsupported settings, or gaps that could weaken the mail server’s front door. In real operations, it supports post-update validation and routine hardening. In incident response, it can also help separate normal maintenance problems from signs that a host may need deeper investigation, because a stable configuration does not prove the server is uncompromised, but it does provide a reliable baseline for further checks.