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The third message is a special one in that it automatically triggers a change of subscription status. For this reason, it is handled separately in MailUp by using the Inactive recipients management area of the Settings > List settings > Preferences page. See managing inactive recipients for details on the settings found on that page. This is an important feature as it allows you to gradually remove from your list recipients that you have not been able to re-engage.
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While you are running your re-engagement campaign, you could consider reducing the mailing frequency of your "regular" campaigns sent to inactive recipients (the same recipients that you are trying to re-activate). This will have a positive impact on your average engagement as inactive recipients will be "skipped" in some of your regular campaigns. In MailUp there are settings that allow you do to so under managing inactive recipients.
Step 4: Evaluate your re-engagement campaign
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