As of 2024/2025, by Microsoft for modern OSes (Windows 10/11/Server 2019+). Key limitations:
The is a lifecycle management tool designed to help IT professionals and developers identify and resolve software compatibility issues when migrating to new versions of Windows (specifically Windows 7 and Vista). Although it is a legacy tool replaced by the Windows Assessment and Deployment Kit (ADK) , its core components—like the Compatibility Administrator —are still used for "shimming" older apps on modern systems. Core Components Application Compatibility Toolkit (ACT) - Win32 apps microsoft application compatibility toolkit 5.6
is a lifecycle management tool designed to help IT pros and independent software vendors (ISVs) assess, mitigate, and manage application compatibility issues before deploying a new version of Windows or a Windows Update. Unlike basic "run-as-administrator" fixes, ACT provides a systematic methodology to identify why an app fails (e.g., hardcoded paths, deprecated APIs, privilege assumptions) and apply targeted shims or fixes. As of 2024/2025, by Microsoft for modern OSes
If you are looking to use this toolkit today (perhaps for a legacy migration project), here is the standard workflow: Operational Phases
Analyzes application installers to identify potential issues that might prevent successful deployment on newer operating systems. Operational Phases