Error conditions

The command SimpleMail fails if the mail server reports an invalid recipient. In that case, the mail message is not sent. This is the safest approach as it does not ignore errors.

To send mail to a list of recipients, use a separate SimpleMail command for each recipient to handle possible errors.

The command SimpleMail only validates recipients against the local mail server. This catches errors such as badly formatted email addresses, but it does not catch non-existent remote addresses. In other words, the validation does not guarantee that a message is delivered to the destination.