Congratulations esnail! With free services, adding an email address on your safe list, white list, or contacts tends to help with mail getting through from those addresses - especially if they are normally placed in a spam box or even disregarded and not delivered all together.
One thing is for sure and that is that it won't do any harm to add addresses you want mail from to your safe / white / contact lists. Also, don't forget if it is a newsletter to urge people when signing up to it to add your newsletter address or even emails from your domain to their safe / white / contact lists
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