When I attempt to access the Lernout & Hauspie TruVoice Text-To-Speech Engine modes from the Microsoft Speech SDK tools, I get a message indicating that a password is required.

The text-to-speech engine included with Microsoft Agent does not support direct SAPI access. You can access the engine only by using the interfaces supported by Microsoft Agent. If you want to program the Lernout & Hauspie TruVoice Engine with Microsoft SAPI, contact Lernout & Hauspie.