If you or a user is getting this 5.7.1 error, it means the message has been blocked for violating the Sender Policy Framework (SPF) policy of a major email receiver (for example, AOL).
MailChannels proactively enforces the SPF policies of certain major email receivers because of widespread abuse by spammers who spoof (i.e. impersonate) email users from these services. If you or a user is blocked with this error, there are two options you can choose from to resolve this issue:
- Change the sending email address to an address on a different domain - in most cases, this error occurs because a user has misconfigured their system to send from a Google, AOL, or Yahoo! account address, which is an SPF violation.
- Send the message using the email services of the sender's domain - for example, if you are sending from a yahoo.com address, use Yahoo! mail servers for this purpose. This method is in keeping with the sender domain's SPF policy.
In cases where a user is unable to change their policy, please submit a request to add an exception to our list.