Exchange Server 2010 supports Internet Message Access Protocol 4
(IMAP4) and Post Office Protocol 3 (POP3). IMAP4 is a protocol for
reading mail and accessing public and private folders on remote servers.
Clients can log on to an Exchange server and use IMAP4 to download
message headers and then read messages individually while online. POP3
is a protocol for retrieving mail on remote servers. Clients can log on
to an Exchange server and then use POP3 to download their mail for
offline use.
By default, POP3 (version 3) and IMAP4 (rev 1) are configured for
manual startup. Because Outlook Web App, Exchange ActiveSync, and
Outlook Anywhere offer so much more than POP and IMAP, they are the
preferred way for users to access Exchange Server. If you still have
users who want to use POP3 and IMAP4 to access Exchange Server, you can
configure this, but you should try to move these users to Outlook Web
App, Exchange ActiveSync, or Outlook Anywhere.
Enabling the Exchange POP3 and IMAP4 Services
Clients that retrieve mail using POP3 or IMAP4 send mail using Simple
Mail Transfer Protocol (SMTP). SMTP is the default mail transport in
Exchange Server 2010. To enable POP3 and IMAP4, you must first start the
POP3 and IMAP4 services on the Client Access servers that will provide
these services. You
must then configure these services to start automatically in the future.
You should also review the related settings for each service and make
changes as necessary to optimize the way these services are used in your
Exchange organization.
You can enable and configure POP3 for automatic startup by completing these steps:
-
Start the Services utility by clicking Start, selecting Administrative Tools, and then selecting Services.
-
Right-click Microsoft Exchange POP3, and then select Properties.
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On the General tab, under Startup Type, select Automatic and then click Apply.
-
Under Service Status, click Start, and then click OK.
You can enable and configure IMAP4 for automatic startup by completing these steps:
-
Start the Services utility by clicking Start, clicking Administrative Tools, and then selecting Services.
-
Right-click Microsoft Exchange IMAP4, and then click Properties.
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On the General tab, under Startup Type, select Automatic and then click Apply.
-
Under Service Status, click Start, and then click OK.
You can use Set-Service
to enable and configure POP3 and IMAP4 as well. Use the –StartupType
parameter to set the startup type as Automatic, Manual, or Disabled. Use
the –Status parameter to set the status as Running, Paused, or Stopped.
The following examples enable POP3 and IMAP4 for automatic startup and
then start the services:
Set-Service -Name MSExchangePop3 -StartupType Automatic -Status Running
Set-Service -Name MSExchangeImap4 -StartupType Automatic -Status Running
POP3 and IMAP4 have related IP address and TCP port configuration
settings. The default IP address setting is to use any available IP
address. On a multihomed server, however, you'll usually want messaging
protocols to respond on a specific IP address. To do this, you need to
change the default setting.
The default port setting depends on the messaging protocol being used
and whether SSL is enabled or disabled. For users to be able to
retrieve mail using POP3 and IMAP4, you must open the related messaging
ports on your organization's firewalls. Table 1 shows the default port settings for key protocols used by Exchange Server 2010.
Table 1. Standard and Secure Port Settings for Messaging Protocols
|
PROTOCOL |
DEFAULT PORT |
DEFAULT SECURE PORT |
|---|
|
SMTP |
25 |
587 |
|
HTTP |
80 |
443 |
|
IMAP4 |
143 |
993 |
|
POP3 |
110 |
995 |
In the Exchange Management Shell, you can manage POP3 and IMAP4 by using the following cmdlets:
-
Get-POPSettings
Lists POP3 configuration settings
-
Set-POPSettings
Configures POP3 settings
-
Test-POPConnectivity
Tests the POP3 configuration
-
Get-IMAPSettings
Lists IMAP4 configuration settings
-
Set-IMAPSettings
Configures IMAP4 settings
-
Test-IMAPConnectivity
Tests the IMAP4 configuration
Configuring POP3 and IMAP4 Bindings
The bindings for
POP3 and IMAP4 use a unique combination of an IP address and a TCP port.
To change the IP address or port number for POP3 or IMAP4, complete the
following steps:
-
In the Exchange Management Console, expand the Server Configuration node, and then select the Client Access node.
-
In the upper portion of the details pane, you'll see a list of your
organization's Client Access servers. Select the server with which you
want to work.
-
In the lower portion of the details pane, on the POP3 And IMAP4 tab, you'll see separate entries for POP3 and IMAP4.
-
Right-click POP3 or IMAP4 as appropriate for the protocol you want to work with, and then select Properties. (See Figure 1.)
-
On the General tab, you'll see the last modification date for the
protocol settings as well as the status of the related Exchange service.
-
On the Binding tab, you'll see the currently assigned IP addresses
and ports used for TLS or unencrypted connections and SSL connections.
The default configuration is as follows: POP3 and IMAP4 are configured
to use all available IPv4 and IPv6 addresses, POP3 uses port 110 for TLS
or unencrypted connections and port 995 for SSL connections, and IMAP4
uses port 143 for TLS or unencrypted connections and port 993 for SSL
connections.
-
Select the Binding tab. To configure IP addresses and ports for TLS
or unencrypted connections, use the following options on the TLS Or
Unencrypted Connections panel:
-
Add Adds a TCP
port on a per-IP address basis or all unassigned IP address basis. Click
Add, and then specify the IP address and port you want to use.
-
Edit Allows you to edit the IP address and port settings for the currently selected entry in the Address list box.
-
Remove Allows you to remove the IP address and port settings for the currently selected entry in the Address list box.
Note
The IP address/TCP port combination must be unique. You can assign
the same port as long as the protocol is configured to use a different
IP address. You can also assign the same IP address and use a different
port.
-
To configure IP addresses and ports for secure connections, use the
following options on the Secure Sockets Layer (SSL) Connections panel:
-
Add Adds a TCP
port on a per-IP address basis or an all-unassigned IP address basis.
Click Add, and then specify the IP address and port you want to use.
-
Edit Allows you to edit the IP address and port settings for the currently selected entry in the Address list box.
-
Remove Allows you to remove the IP address and port settings for the currently selected entry in the Address list box.
-
Click OK to save your settings. When you add new ports, you must open
the related messaging ports on your organization's firewalls.
-
Use the Services utility to restart the Exchange POP3 or IMAP4 service. Restarting the service applies the new settings.
