Email providers such as Gmail, Outlook, and Yahoo use authentication checks to protect users from spam, phishing, and spoofing attacks.
If you send emails from an unauthenticated domain, your messages are more likely to:
By authenticating your domain, you authorize FastCommerce to send emails on behalf of your business. This improves inbox placement, strengthens your sender reputation, and helps build customer trust.
To comply with modern email provider requirements and help ensure reliable email delivery, FastCommerce sends campaign emails only from authenticated domains.
If you use a public email service such as Gmail, Yahoo, Outlook.com, or Hotmail, your email address cannot be authenticated because these providers do not support custom sender authentication.
Likewise, if you use your own domain but do not complete domain authentication, FastCommerce cannot verify that it is authorized to send emails on your behalf.
In either case, FastCommerce will automatically replace your sender address with a FastCommerce-managed email address, such as:
store+12345@fastcommercemail.com
This allows FastCommerce to send your campaigns through an authenticated domain, helping improve deliverability and reducing the likelihood that messages will be rejected or marked as spam.
Although your emails can still be delivered successfully, recipients will see the FastCommerce-managed sender address instead of your branded domain. This may reduce brand recognition and customer trust compared to sending from your own authenticated domain.
For the best customer experience, brand consistency, and email performance, we strongly recommend authenticating your sending domain before sending campaigns.
Domain authentication and email verification are separate processes.
Every sender email address must be verified before it can be used for campaigns.
Verification confirms that you have access to the email address and permission to send emails from it.
This process is typically completed by clicking a verification link or entering a verification code sent to the email address.
Email verification is required, but it does not improve email deliverability.
Domain authentication verifies ownership of your domain and authorizes FastCommerce to send emails on your behalf.
This process requires DNS configuration and helps improve sender reputation and email deliverability.
For best results, complete both email verification and domain authentication.
Domain authentication can only be completed for domains that you own and control.
Examples of supported sender addresses:
marketing@yourcompany.com
support@yourcompany.com
hello@yourbrand.com
Public email services cannot be authenticated, including:
Gmail
Yahoo Mail
Outlook.com
Hotmail
If you use a public email address or an unauthenticated domain, FastCommerce will send your campaigns using a FastCommerce-managed sender address rather than your own domain.
To authenticate your domain, FastCommerce generates three DNS records:
Two CNAME records (used for DKIM authentication)
One TXT record (used for DMARC authentication)
These records allow receiving mail servers to verify that FastCommerce is authorized to send emails on behalf of your domain.
Before authenticating your domain, make sure your sender email address has been verified.
Navigate to Email Campaigns
Click Settings
Locate the Authenticate Your Sending Domain section
FastCommerce will display the DNS records required for authentication.
Copy the Name and Value fields exactly as shown.
Log in to your domain provider or DNS hosting service and create the DNS records using the values provided by FastCommerce.
Common DNS providers include:
GoDaddy
Cloudflare
Namecheap
Squarespace
Wix
Bluehost
Google Workspace
After saving your DNS records, click Authenticate Now.
FastCommerce will automatically validate the records.
Most DNS changes are detected within a few minutes, although DNS propagation may take up to 48 hours depending on your provider.
You may see one of the following statuses:
Your DNS records have not yet been detected, or authentication has not been completed.
Your domain has been successfully authenticated and is ready to send email campaigns using your branded sender address.
No.
Domain authentication is only available for domains that you own and control.
Public email services such as Gmail, Yahoo, Outlook.com, and Hotmail do not support custom sender authentication and cannot be authenticated.
If you use one of these services, FastCommerce will send campaign emails from a FastCommerce-managed sender address.
We recommend:
Verifying all sender email addresses before use
Authenticating your sending domain before sending campaigns
Using a branded domain for marketing emails
Configuring DNS records exactly as provided by FastCommerce
Avoiding public email addresses for campaign sending
Completing domain authentication helps maximize deliverability, improve sender reputation, maintain consistent branding, and provide a more professional experience for your customers.