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XPhone E-Mail Server (LUMI) SMTP - Frequently Asked Questions / Solutions


This article discusses problems with sending mail from the integrated XPhone Connect e-mail server to the configured e-mail gateway.

What are the possible causes if the following error patterns occur:

  • A test e-mail does not arrive when it is sent in the administration interface.
  • The XPhone user does not receive a mail in the case of a missed call, although the function is activated.
  • The XPhone user does not receive a mail when a new fax/voicemail/SMS is received, although the integration is configured to "Groupware Client".
  • In the SMTP inbox log of the UM services only such messages are found

//----- Sys: 'Session:'a38246f0-6b64-19a8-d777-38595242263a added 01.01.2021 12:00:00

//----- Sys: 'Session:'a38246f0-6b64-19a8-d777-38595242263a removed 01/01/2021 12:00:00

Check the following points to solve the problem:

1) Make sure that the configuration of the external email server is correct and complete in the administration interface under System Settings > External Email Server.

2) The XPhone Connect Server's internal e-mail server, also called LUMI, occupies the default SMTP port 25. If another application on the XPhone Connect Server occupies this port, change the LUMI's SMTP port in the administration interface under System settings > External e-mail server > Advanced settings and edit the IntegratedPortSmtp parameter. For example, 2525 can be configured as the alternate port.

Afterwards restart the UM services and check if the process IsMailServer.exe is started.

3) It may happen that the wrong IP address is selected during the automatic configuration of the LUMI. Store the correct IP address of the XPhone server under System settings > External e-mail server > Advanced settings for the IntegratedMailserver parameter.

Then restart the UM services.

4) Store the IP address of the XPhone Connect server in the UM settings under UM > Fax > General, UM > Voicemail > General and UM > SMS > General. To do this, switch from "Automatic" to "Manual" in the drop-down menu and enter the IP address. Save the settings and restart the UM services afterwards.

5) Check if the external e-mail server is reachable. To do this, open the command line and enter the following command

telnet IP.of.mail.server 25

The external mail server must respond with a message "SMTP Server Ready". If this is not the case or an error message appears, then no mail server is reachable on the checked IP socket. If the correct answer comes, you can still test with the commands helo and ehlo name whether the mail server responds. If after typing the first letter of the command the telnet session turns black, then the external mail server rejects any commands.

As a counter test, run the same command for the LUMI in general and its SMTP receiver services to verify that the LUMI is running correctly:

telnet IP.of.XPhone.Server 25

telnet IP.of.XPhone.Server 2533

telnet IP.of.XPhone.Server 2544

Again you can test with the commands helo and ehlo name.

6) Check if all permissions and routing settings are available in the Mail Server Manager.

To do this, navigate to the XPhone Server installation directory:

C:/ProgramFiles/C4B/XPhone Connect Server/MailServer/.

And start the "MailServerManager.exe" there.

Then compare your settings in the "Security" section with this screenshot and add any missing entries. Especially important are the three yellow marked entries above.

Mail Server Manager Security Einstellungen

The yellow-marked, concrete IP addresses may differ from your system.

Check the routing settings at the same time to see if the two entries are present:

Mail Server Manager Routing

Restart the UM services after completing the entries.

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