The Microphone Setup Wizard insures that the user's microphone is plugged in and working. Applications using speech recognition should give the user an opportunity to run this.
To run the Microphone Setup Wizard, the application does a CoCreateInstance on the wizard's object, CLSID_STMicWizard, and queries for the ISTMicWizard interface. It then calls ISTMicWizard->Wizard(), with a set of flags specific to the application.
The Microphone Setup Wizard understands only ISTMicWizard.