Validation Automation
You can use the Evalcom2.dll to implement validation operations for installation packages and merge modules.
The following sections of this documentation contain information about using Windows Installer validation from within authoring tools:
It is recommended that Evalcom2.dll be installed using the Windows Installer. The Orca.msi package provided with the Microsoft Windows Software Development Kit (SDK) for Windows XP with Service Pack 2 (SP2) or greater installs Evalcom2.dll. The component ID for the component that contains the COM interface is {53315473-B8D6-470A-9951-D9AE5C11FC91}.
For information about obtaining the Windows SDK, see Windows SDK Components for Windows Installer Developers.