Setting the Return-Path: (Bounce) Address
The Return-Path: address specifies where bounce notifications should be sent and is set with the setReturnPath() method of the message.
You can only have one Return-Path: and it must not include a personal name.
To set the Return-Path: address:
Call the setReturnPath() method on the Message.
Bouce notifications will be sent to this address.
$message->setReturnPath('bounces@address.tld');
Parent topic: Specifying Sender Details
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