Unregisters a registered speech synthesizer or voice.


OSErr SpeechSynthesisUnregisterModuleURL(CFURLRef url);



The file URL of the synthesizer plug-in or voice to unregister.

Return Value

A result code. See Result Codes.


The SpeechSynthesisUnregisterModuleURL function unregisters the speech synthesizer or voice specified by url. When a synthesizer is unregistered, all voices that require that synthesizer are automatically unregistered.

Note that if a speech channel is currently using a synthesizer or voice that becomes unregistered, the speech channel is considered inactive and will return an error when the application tries to access it.

An application that called SpeechSynthesisRegisterModuleURL to register a synthesizer or voice should do the following if the volume containing the synthesizer or voice is about to be unmounted:

  • Call DisposeSpeechChannel to dispose of each speech channel that uses the synthesizer or voice

  • Call SpeechSynthesisUnregisterModuleURL to unregister the synthesizer or voice

If you call SpeechSynthesisUnregisterModuleURL to unregister a synthesizer or voice and you receive either the noSynthFound or voiceNotFound result codes, it means that the synthesizer or voice is not currently registered.

See Also

Registering and Unregistering Synthesizers and Voices


Registers and makes available a speech synthesizer or voice.