To prevent a task from closing while there are still unsent emails or documents, ensure that your workflow configuration includes phase guards for pending document deliveries. Typically, this involves setting conditions or using validation rules within your workflow management system to verify that all required communications have been sent before allowing the task to close. See the article Phase Guards for more information.

You can configure the subfeature Document delivery required to specify which phases a document delivery channel must be present and ready to send. For more details, see the Global Features article Document Delivery.