Problem In Kurzweil, you do not hear any voices yet can hear sound in other applications. You may be able to see that the voices are installed. Also, the application may work on another user account. Solution Reinstall SAPI Runtimes.
Reinstalling the SAPI runtimes can fix problems in an application using text to speech: Download and Install SAPI 4. Download and Install SAPI 5. Restart the Computer.