Configure Sender Validation and Email Authentication

Before creating and sending email campaigns it is mandatory to have a validated email address. Sending campaigns from an unvalidated email address is not possible. Email Authentication on the other hand is not mandatory, but it's recommended in order to increase deliverability. 

The following article will show you how to set up Sender Validation and Email Authentication and their related settings.

Sender Validation

  1. To set up Sender Validation, go to the Settings > Add or remove senders section of your account.

  2. To validate a new email address, click on the Add a new sender button. If you have an already existing email address that hasn't been approved yet, a Resend approval email button will appear in front of it. Click on it to request approval again.

  3. When you click on the Add a new sender button, a pop-up will appear where you will need to enter the new email address and then click on Request approval.

  4. A confirmation email will be sent to the email address you have entered where the owner of that address can give their consent.

  5. Once the owner of the email address has clicked on the Verify my email address button in the confirmation email, a tick icon will appear in front of it and you can now use that email to create and send campaigns. 
  6. Click on the star button to mark an email address as default. The marked email address will be set as default when creating a new campaign. If you would like to remove an existing email address, click on the Remove sender button to the right of the email address and confirm the removal.

Email Authentication

  1. To set up Email Authentication, go to the Settings > Add or remove senders section of your account.

  2. Click on Set up authentication button next to the desired domain.

  3. A pop-up featuring the email authentication settings will open up. If the box containing the record is coloured green, authentication for your domain has been set to active and you no longer need to take action. If the box featuring the record is coloured red, your domain administrator will need to create the record in question to activate authentication. 
  4. The SPF and DMARC record are created automatically and should only be added to the DNS by the domain administrator.
  5. The DKIM key needs to be generated first. To achieve that, you need to choose a selector. You can leave the default selector 'flexmail' or change it to the desired name. Click on the Generate DKIM keys button below the selector. 

  6. Finally, click on the Generate report button. A TXT file will be automatically downloaded. You can then forward this report to your domain administrator. 


It can take up to 24-48 hours for the records to be completed and turn green after adding them to the DNS.

Are you a customer at Combell? Great! Here you will find all the instructions to set up the authentication in your control panel. Can't find this part? Mail to

Can't do it or are you afraid of doing something wrong? Then send your generated records to, they know what to do. 

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