Enabling and configuring the POP3 service port

For POP3 clients to access mail files on the server, you must enable a POP3 port on the server. You can enable the TCP/IP port, the SSL port, or both. By default, the Domino® POP3 service uses TCP/IP port 110. This topic explains how to enable and disable the POP3 port, how to set the POP3 service to use a nonstandard port, and how to change security options for the port.

Configuring POP3 authentication options on servers that use Internet Site documents

About this task

On servers that use Internet Site documents, the POP3 service obtains port authentication settings from the Security tab of the POP3 Site document, rather than from the Server document. As a result, when Internet Site documents are used, the TCP/IP and SSL port authentication settings described in the procedures that follow are not available in the Server document. Settings in the Server document still provide the port numbers and status for the POP3 TCP/IP and SSL ports, and enable the POP3 ports to honor server access restrictions.

To determine whether the use of Internet Site documents is enabled for a server, check the value of the Load Internet configurations from Server\Internet Sites documents field on the Basics tab of the Server document. If this field is set to Enabled, the server uses Internet Site documents to configure all of its Internet protocols (POP3, IMAP, SMTP, and so forth).

If the server uses Internet Site documents, then you must use Site documents to configure all Internet protocols on the server. If a POP3 Site document is not present in the Domino Directory, or the authentication options in a configured POP3 Site document are set to No, users cannot connect to the POP3 service. In each case, POP3 clients receive the error This site is not enabled on the server when attempting to connect to the POP3 service:

To enable the POP3 TCP/IP port

About this task

On servers with multiple TCP/IP ports, by default, the POP3 service uses the port listed first in the NOTES.INI file as the preferred path. If you want the service to use a port other than the default one, you can configure it to use a specific port.

Procedure

  1. From the Domino Administrator, click the Configuration tab and then open the Server document for the server that runs the POP3 service.
  2. Click the Ports > Internet Ports > Mail tab.
  3. To enable the default TCP/IP port, in the Mail (POP) column, change the value of the TCP/IP port status field to Enabled.
  4. Click Save and Close or edit additional settings, as directed in the following procedure.

To configure the POP3 TCP/IP port

Procedure

  1. From the Domino Administrator, click the Configuration tab and then open the Server document for the server that runs the POP3 service.
  2. Click the Ports > Internet Ports > Mail tab.
  3. In the Mail (POP) column, complete these fields, and then click Save and Close:
    Table 1. POP3 TCP/IP fields

    Field

    Enter

    TCP/IP port number

    Choose 110 (default) to use the industry standard port for POP3 connections over TCP/IP. You can specify a different port, but 110 works in most situations. When specifying a nonstandard port, make sure the port is not reserved for another service. Port numbers can be any number from 1 to 65535.

    TCP/IP port status

    Choose one:

    • Enabled (default) - Allows POP3 clients to connect to the Domino server without using SSL. Users must provide their name and Internet password to connect.
    • Disabled - Prevents POP3 clients from connecting to the Domino server, unless they can connect using SSL.

    Enforce server access settings

    Choose one:

    • Yes - Access to the POP3 service is controlled by the server access settings on the Security tab of the Server document. Users who are not allowed to access the server cannot access mail through the POP3 service.
    • No - (default) The POP3 service ignores the server access settings in the Server document.
  4. Restart the POP3 task to put the new settings into effect.

To enable and configure the POP3 SSL port

Before you begin

Familiarize yourself with the Domino security model and set up SSL on the Domino server.

Procedure

  1. From the Domino Administrator, click the Configuration tab and then open the Server document for the server that runs the POP3 service.
  2. Click the Ports > Internet Ports > Mail tab.
  3. In the Mail (POP) column, complete these fields, and then click Save and Close:
    Table 2. POP3 SSL port fields

    Field

    Enter

    SSL port number

    Choose 995 (default) to use the industry standard port for POP3 connections over SSL. You can specify a different port, but 995 works in most situations. When specifying a nonstandard port, make sure the port is not reserved for another service. Port numbers can be any number from 1 to 65535.

    SSL port status

    Choose one:

    • Enabled - Allows POP3 clients to connect to the POP3 service over SSL.
    • Disabled - (default) Prevents client connections over SSL.

    Authentication options: Client certificate

    If SSL port status is set to Enabled, choose one:

    • Yes - The POP3 SSL port authenticates POP3 clients that use client certificates. If a connecting client does not have a certificate, the server reverts to using name-and-password authentication.
    • No - (default) The POP3 SSL port does not support client certificate authentication.

    Authentication options: Name & password

    If SSL port status is set to Enabled, choose one:

    • Yes - POP3 clients use name-and-password authentication when connecting to the POP3 service over SSL.
    • No - (default) The POP3 SSL port does not support name-and-password authentication.
  4. Restart the POP3 task to put the new settings into effect.

Performing additional POP3 configuration

About this task

In addition to configuring the POP3 service port, you can customize the operation of the POP3 service by setting variables in the server's NOTES.INI file. Variables used to configure the POP3 service begin with the prefix POP3.