Resolve a DMARC error with Infomaniak email

This guide helps you solve various issues related to the implementation and use of a DMARC policy with your email.

Refer to this other guide if you encounter a DMARC issue specifically when using Google services.

DMARC error or rejection...

...during a redirection even though the initial destination address was able to receive the email (SPF error)

Email redirection without SRS causing an SPF error

Let's say you have set up an email redirection from your email address "user@example2.com" to your new address "user@yourdomain3.com", without using SRS. When someone sends an email to "user@example2.com", it is automatically redirected to "user@yourdomain3.com". Example:

• sender: john.doe@gmahoo1.com
• initial recipient: user@example2.com
• final destination: user@yourdomain3.com (SPF error)

In schematic termsWhen John sends an email to "user@example2.com", the email is redirected to "user@yourdomain3.com". However, the mail server of "yourdomain3.com" still sees the email as coming from "john.doe@gmahoo1.com".

In detailWhen John sends an email to "user@example2.com", the email is redirected to user@yourdomain3.com" that is to say that the envelope sender address will remain john.doe@gmahoo1.com but the envelope recipient address will be changed to user@yourdomain3.com.

This will generate an SPF error, because the SPF of the gmahoo1.com domain does not authorize the IP addresses of the example2.com SMTP servers to send emails for its domain.

This SPF error will cause the DMARC rejection.

If you want the redirection to work without error, it is necessary for the provider of the email address that is redirecting to perform the redirections with SRS.

How does email redirection work at Infomaniak?

When you receive an email on an Infomaniak address and it is redirected to another email address, the sender's email address is rewritten to reflect the redirection. Thus, the recipient's mail server sees the email as coming from your own domain.

In summary, the use of SRS in email redirection helps maintain the integrity and security of emails while ensuring that authentication mechanisms such as SPF and DKIM remain valid.

...related to an incorrect DNS entry

Malformed DMARC Record: if the DMARC record is not correctly formatted, this can cause errors. Make sure that the tags and values are correctly specified.

Invalid DMARC Policy: errors may occur if the specified DMARC policy is not correct. The possible values for the policy are "none", "quarantine" and "reject". An incorrect value can cause issues.

Multiple DMARC entries: having more than one DMARC entry in the DNS zone is considered an error.

If you have multiple DMARC records, mail servers may interpret this differently, which can lead to unpredictable behavior. Fix this by consolidating your DMARC settings into a single entry.

Check your current DMARC entry using dedicated tools like those below:

• https://dmarcadvisor.com/dmarc-check
• https://mxtoolbox.com/dmarc.aspx

...related to a send that does not comply with SPF and/or DKIM

A DMARC error or rejection related to SPF or DKIM can occur if the SPF or DKIM authentication mechanisms are not correctly configured or if they are not aligned with the domain's DMARC policy.

This can for example happen if you send an email from your Infomaniak email address using another provider's SMTP server. To resolve this issue:

• Check the overall security of the Mail Service.

I send an email from my Infomaniak address and I receive an error email of type "Reject DMARC

To resolve this issue:

• Check the overall security of the Mail Service.
• Perform a send test from the Webmail mail.infomaniak.com and/or check the server settings of the email software/client.

I send an email from an external email address (Microsoft, Google, Yahoo, Orange, …) and Infomaniak rejects my email with a DMARC error

To resolve this issue:

• Check with the sender's email provider to ensure that emails are sent according to their configuration recommendations and, if necessary, contact the sender's email provider for more information.

I want to receive an email at my Infomaniak address but the sender informs me that they receive a DMARC error when sending to my address

To resolve this issue:

• In this case, the email was blocked due to a violation of the DMARC policy that the sender has implemented on their domain; it is necessary for the sender to contact their email provider or the administrator of their service to inform them of the situation.