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If you cannot change the SPF record for your email domain, you still have the option of using the default sender address Survey <noreply@customervoice360.com>. Just create a new mail sender, as described above, using the email address noreply@customervoice360.com, and enter the name of your company as a realname instead of "Survey", for example.
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Using List-Unsubscribe Header
Another way to reduce the likelihood of your emails ending up in the spam folder is the List-Unsubscribe Header option. You can add a link in Email templates that participants can use to unsubscribe from automatic emails.
Proceed as follows to set this up:
Expand the Advanced mail settings area in your mail template.
In the free text field next to List-Unsubscribe Header, insert a valid link to a website that participants can use to unsubscribe. You can also enter the following placeholders in the field:
#unsubscribe_survey#: Link in the email that deactivates further emails for this survey
#unsubscribe_global#: Link in the email that deactivates further emails for all communication
Click on Save to apply your changes.
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