Emails Not Being Sent – SMTP 5.7.0 Denied

[Stephen-CT]

We are experiencing an issue where any emails are not being sent from 3CX.

When trying Test your email server configuration, it fails with 5.7.0 Denied. The event log shows Severity: Error, Event ID: 50026, with 5.7.0 Denied”.

No configuration changes were made prior to the issue. The FQDN resolves correctly to the proper public IP, the public IPs used by 3CX SMTP are allowed on the firewall, and the SMTP configuration is correct. The 3CX license is active and was reactivated successfully with no errors. The system is using the 3CX SMTP server, which was working previously, and all 3CX services have been restarted, but the issue persists.

Any guidance would be greatly appreciated. Thank you!

 

[NikosK_3CX]

Please make sure that your FQDN IP and the external IP are the same.
After that, you can retry the test for the SMTP.

 

[Stephen-CT]

Please make sure that your FQDN IP and the external IP are the same.
After that, you can retry the test for the SMTP.

I have verified that the FQDN resolves to the same public IP, so they match.

Could there be another reason for the 5.7.0 Denied error?

 

[Kevin Attard Compagno]

We've checked, and we see differences, but we won't expose any IP Address details here. Speak to support please.

 

[bitn2]

I have verified that the FQDN resolves to the same public IP, so they match.

Could there be another reason for the 5.7.0 Denied error?

Your pbx ip isnt the same for in and outbound. Thats 99% the reason why its not working.