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Once expanded, there is a check box called "Campaign exclusively destined to business contacts" Marking this check ensures that the emails will be sent to everyone in the target that has chosen to receive emails and additionally include those that have not stated any preference (but not to those who have marked "No").
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There is no specific setup necessary. The contact´s email preferences are located in the Contact file>Marketing tab. If the options are not marked (see below) the email will be sent. If either of these two options are marked "no" the email will not be sent.
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