Not receiving any email from 3CX Phone system

[ABSHSupprt]

Hello,

One of my clients is not receiving reports

I have checked the SMTP and it is working properly

In the past one of my users was blocked in our server

 

[Gino2022]

Are you using the 3CX SMTP Server?

When you set up M365 integration it switches the sender to your M365, which has caught us out when we've set up the integration using a Microsoft Admin account without a mailbox to send through.

 

[ABSHSupprt]

We are using the 3cx smtp

We tested different accounts on our tenant, but there is only one that is not working

 

[Fabian Jsn]

please makesure open this port from your firewall

• SMTP Service: Cloud Service for SMTP Messages
  smtp-proxy.3cx.net, 2528 (outbound, TCP)

reference https://www.3cx.com/docs/manual/firewall-router-configuration/

 

[Alphabetic]

with 3CX SMTP they will send an email to this user.

if this user doesnt exist when this email is sent, then 3CX will stop sending to this email for several days.

you will have to wait it out..

or...

if the email now exists just use plus addressing

[email protected] and see if it comes through.

 

[ABSHSupprt]

Hi

Thank you for your reply

-please make sure open this port from your firewall -->as previously mentioned, we are only facing issues with one specific email account
-if this user doesnt exist when this email is sent, then 3CX will stop sending to this email for several days. -->the email existed and used to receive emails, then it stopped working

We have reviewed o365,we ran tests with different email addresses, we can see traffic with other accounts, but with the one account, no email received (no blocked, no dropped)


Seems like 3CX may have blocked this user's account for some reason

 

[Alphabetic]

Did you read anything I said?