But if you package MSI files in your software, you can use basic VBScript to create a "shell" object that runs Windows commands, including executing these MSI files.

How to Use VBScript to Rename Files. Many commercial Web sites use the VBScript language to create flexible, dynamic pages. In some applications, such as a site that lets you download business ...

Renegade's Random Tech weblog has a simple how-to for converting batch or .VBS scripts into executable forms using a lesser-known Windows program called IExpress.