Sending' reported error (0x80042109) from Outlook

[romanepo]

xxxxx.com domain cant send mail from mail client outlook ,but when try to check yyyyy.com domain can sending mail.
Both domain located in same server.
When i change xxxxx.com domain smtp port from 25 to 587 than it working and another domain yyyyy.com working default port 25.

I cant understand why occurring this issue.
xxxxx.com outlook error report

Task '[email protected] - Sending' reported error (0x80042109) : 'Outlook cannot connect to your outgoing (SMTP) e-mail server. If you continue to receive this message, contact your server administrator or Internet service provider (ISP).'

 

[cPanelMichael]

Hello

Did you perform all of those tests from the same computer, email client, and Internet connection?

Thank you.

 

[romanepo]

Hello

Did you perform all of those tests from the same computer, email client, and Internet connection?

Thank you.

Yes ,it was performed same computer, email client, and Internet connection

 

[cPanelMichael]

Check to see if the issue persists on another email client such as Thunderbird in order to rule out any issues with Outlook itself.

Thank you.

 

[visakhbc]

If the same user can connect through port 587, we can safely rule out firewall misconfigurations at PC or server end. Then the only real possibility exists at ISP. The most common cause is port 25 blocks by ISPs. This is one of the main reasons why cPanel has an optional second SMTP port.