Unsuccessfully Transferring the Call
If the Call Redirect step registers the destination extension as out of service, the script executes the Unsuccessful output branch.
Configure the Unsuccessful output branch of the Call Redirect step to set the value of the prefixPrompt variable to inform the caller that the extension was out of service.
The Unsuccessful output branch of the Call Redirect step contains the Set step. Configure the Unsuccessful output branch of the Call Redirect step by dragging a Set step from the General palette to the Design pane, and dropping it over the Unsuccessful icon under the Call Redirect step, as shown in figure Call Redirect Output Branch Scripting. Then configure the Set step to set the value of the prefixPrompt to play back a message to the caller that the extension is out of service.