Email issue with External Domain

[AkshayBhoir31]

Dear All.

Please help us to resolve email issue with our domain zclchemicals.com. some of our customer domain emails get blocked when we send from our domain. we have checked error from both end but no issue found. all the records found OK. please find below error.

Google tried to deliver your message, but it was rejected by the server for the recipient domain <a href="" target="_blank">customer website</a> by <a href="http://mx1.hc212-78.ca.iphmx.com" target="_blank">mx1.hc212-78.ca.iphmx.com</a>. [x.x.x.x]. The error that the other server returned was: 451 #4.1.8 Domain of sender address does not resolve. The receiving host refused the connection from our servers.“)

[ppreenja]

Hi Akshay,

You are getting this error because at the receiving end sender verification must be "ON" for the emails being received and they are not able to verify your domain.
This error is received when the Envelope Senders' domain is not able to be resolved.

If your domain records are published correctly then you can reach out to the receiving domain to check on their DNS configuration.

I hope that helps!

Cheers,
Pratham

[AkshayBhoir31]

Dear Pratham,

Thanks for your update, this issue we are facing for multiple customers. i have already share this with our customer to check this issue from their end but our customer confirm that their is no issue from their end.

we also check our domain details with google & dns provider but no issue found at our end also.

pls suggest any solution to resolve this issue.

[ppreenja]

Hello Akshay,

If the above information is not able to help resolve the issue then I would suggest opening a TAC case with Cisco to get the issue resolved.

Cheers,
Pratham