How do I customize the confirmation email? Watch video
Locate the Your current campaign field in the upper-right corner of the screen and click the down arrow to display the drop-down list. Click the settings gear icon to the right of the campaign you wish to adjust the confirmation message for.
In the Permission tab scroll down to the Customize confirmation message. Click this button to choose the body template, add your own text and signature. In the Confirmation message select the From field and subject (or create custom one).
When the customer confirms their subscription, they are added to your contact list and begin receiving information from you.
Note: The language for the confirmation message can be selected in the General tab under Campaign Language list.
If you do not want to send the confirmation messages, you need to enable single opt-in, the instructions can be found here.