Several weeks ago I started receiving “Undelivered Mail Returned To Sender” replies for every email I have sent to yahoo.com and aol.com customers. All other domains seem to be working fine. Here is an example of the message embedded in the returned email (note tthey are all the same except for the email address of the sent email):
Message temporarily deferred due to unresolvable RFC.5321 from domain. See
[https://senders.yahooinc.com/error-codes#unresolvable-from-domain](https://senders.yahooinc.com/error-codes#unresolvable-from-domain) (in reply
to end of DATA command)
Note that I went to the referenced URL and it says this about the error:**
Unresolvable RFC.5321 or RFC.5322 from domain**
These errors indicate that the domain used to the right of the @ in the MAIL FROM or HEADER FROM does not appear to be valid.
We determine if the domain name exists by using an SOA query; therefore, if multiple subdomains are used in MAIL FROM or HEADER FROM commands, then besides setting up a DNS A or MX record (perhaps using a wildcard), then SOA records must be set up as well.
These errors can be returned as either a timeout/servfail (451) or a permfail (554)
This seems to only be an issue with Yahoo and aol. To my knowledge I do not have multiple subdomains. Please fix.
It sounds like you’re experiencing a common issue with email delivery to Yahoo and AOL domains. The error message you’re seeing indicates that there might be a problem with the sender’s domain configuration, which can lead to temporary deferrals.
Here are a couple of things you can check:
Sender Domain: Ensure that your sending email address is properly configured and that the domain is not blacklisted or misconfigured.
SMTP Settings: If you’re using an external SMTP server, consider switching back to Gigbuilder’s default SMTP, as it’s recommended for reliable delivery.
If these suggestions don’t resolve the issue, our support team can assist you further. Please feel free to reach out for more specific help!
I have not had this issue for years (not since I was provided my own IP address). WeDJ hosts my website and email. I am using the Gigbuilder SMTP server. I don’t know how to fix this. Please fix for me.
I understand how frustrating it can be to deal with undelivered mail issues. Since you’re using the Gigbuilder SMTP server, I recommend checking your Email Replies setting. If it’s set to “Reply to Gigbuilder” only, try changing it to “Reply to Both.” This will ensure that replies land in both your CRM and your personal inbox, which might help with the delivery issues you’re experiencing.
If this doesn’t resolve the problem, please reach out to our support team for further assistance. We’re here to help!
You have – she created a ticket and we just searched through the mail log. solidgoldpro is not sending to yahoo, etc., and something happened on your website around the 10th of April that changed rules. They have been fixed and email to yahoo has been tested and verified. This is why you host with us – we dig deep. Here’s the response from the fix agent: Quick update on the email delivery issue you’ve been running into with Yahoo and AOL addresses. Our mail server authenticates every outgoing message with a digital
signature (DKIM) so receiving providers know the mail really came from your domain. The signature covers both the headers and the message body, and it has to match
what actually arrives at the far end — byte for byte, including invisible characters like line breaks. Somewhere around April 10th, Yahoo and AOL tightened their
signature-validation rules, and our server’s signing configuration turned out to be slightly too strict about how it handled the formatted HTML bodies that Outlook
produces for messages with embedded images. The signature was valid when it left your computer, but by the time Yahoo verified it, a tiny formatting difference in
the body was enough to invalidate it. Their system returned an unhelpful error about the sender domain not being resolvable, which pointed us in the wrong direction
for a while.
We’ve now switched our server to the more forgiving industry-standard signing mode that Google, Microsoft, and Amazon all use. Your most recent test to AOL went
through on the first try. Anything you resend from Outlook should deliver normally now. If any of your Yahoo or AOL contacts were waiting on a message that got
stuck, please resend those from your Sent folder so they get a fresh, properly-signed copy. Let us know if you see any further rejections — but you shouldn’t.’