When it comes to auditing Active Directory (AD), there are several free tools available that can help you track changes, monitor events, and ensure compliance. Here are some notable ones:

LepideAuditor Free Edition:

  • This tool provides real-time auditing, reporting, and alerting for Active Directory, as well as other platforms like Exchange Server, Group Policy, SQL Server, and SharePoint.

Netwrix Auditor for Active Directory Free Community Edition:

  • Netwrix offers a free edition of their Auditor tool that provides detailed reports on changes to Active Directory, including user and group changes.

ManageEngine ADAudit Plus Free Edition:

  • This tool offers a limited version of their comprehensive AD auditing solution, providing real-time monitoring, reports, and alerts on changes made in Active Directory.

Spiceworks Network Monitor:

  • While not exclusively for AD, this tool can monitor network-wide activity, including AD-related events. It provides real-time alerts and detailed reports.

SolarWinds Event Log Consolidator:

  • This tool helps collect and consolidate event log data from various sources, including Active Directory, allowing for easier analysis and reporting.

Microsoft Security Compliance Toolkit:

  • While not a tool in itself, it includes various scripts and templates for auditing and securing Active Directory environments. It’s a set of best practices from Microsoft.

PowerShell Scripts:

  • Microsoft provides a wide range of PowerShell scripts that can be used to audit Active Directory. These scripts can be customized to fit specific needs.

Windows Event Viewer:

  • While not as robust as third-party tools, the built-in Event Viewer in Windows allows you to view and filter security logs, providing basic auditing capabilities.

ELM Event Log Monitor:

  • ELM Event Log Monitor is a lightweight tool that can monitor and alert on Windows event log changes, including those in Active Directory.

Remember that while these tools can be helpful, they often have limitations compared to paid solutions. It’s important to choose a tool that aligns with your specific auditing needs and compliance requirements. Additionally, always review the features and limitations of each tool to ensure it meets your expectations.