XF 1.5 Forum Emails blocked


Active member

since today morning our forum emails (registration, message information) are blockend by a specific email hoster, see our server send error message below. The recipient says "the originating IP of the message is not permitted by the domain owner". There are no server or XenForo changes in the last month.

The XenForo configuration is sending with SMTP without authentication. No other params are set. The XenForo standard email adress is NoReply@<forumname.com>, which is connected with no mailbox., users get an error message when replying inadvertently.

Any idea about a possible background of this problem?

Kind regards & thank you in advance

host mx00.emig.gmx.net[] said: 550-Requested action not taken: mailbox unavailable 550-Reject due to SPF policy. 550-The originating IP of the message is not permitted by the domain owner.


XenForo developer
Staff member
This is related to SPF, which is a way of denoting allowed sender IPs via DNS: https://en.wikipedia.org/wiki/Sender_Policy_Framework

It's not something directly related to XenForo, though the email addresses used to send email from XenForo are involved (specifically the return path/envelope sender that is used). You'll need to check the SPF on your domain, assuming your board emails are using that domain on the return path and/or the from header.


Active member
Thank you!

Now I configured the Default Email Address as NoReply@<MyForum.com>, which is a dummy adress which does not exist. And Contact Email Address as info@<MyForum.com>, which does forwarding the emails to another email-box.

But the above error message from the email hoster "The originating IP of the message is not permitted by the domain owner" has not changed. How can I check what XenForo is sending? Are there further possible email configurations in XenForo which are relevant to this problem?

Especially: Where in XenForo is the ReplyTo adress configured?


Active member
Andy, thank you very much. I asked them now for SPF. But what do they have to do?

It seems to me that die ReturnPath adress is identical with XenForo Contact Email Address. Is this correct? The header shows this information.