SMTP Server Setup (IIS 6.0)

The Simple Mail Transfer Protocol (SMTP) service provided by IIS is a simple component for delivering outgoing e-mail messages. Delivery of a message is initiated by transferring the message to a designated SMTP server. Based on the domain name of the recipient e-mail address, the SMTP server initiates communications with a Domain Name System (DNS) server, which looks up and then returns the host name of the destination SMTP server for that domain.

Next, the originating SMTP server communicates with the destination SMTP server directly through Transmission Control Protocol/Internet Protocol (TCP/IP) on port 25. If the user name of the recipient e-mail address matches one of the authorized user accounts on the destination server, the original e-mail message is transferred to that server, waiting for the recipient to pick up the message through a client program.

In the case where the originating SMTP server cannot communicate directly with the destination server, the SMTP service can transfer messages through one or more intermediate relay SMTP servers. A relay server receives the original message and then delivers it to the destination server, or redirects it to another relay server. This process is repeated until the message is delivered or a designated timeout period passes.

The SMTP service is not installed by default. You must install the SMTP service using the Control Panel. Installing the SMTP service creates a default SMTP configuration which you can then customize to your needs using IIS Manager.

Many articles about deploying and configuring the SMTP service are available by searching for "smtp" on the Microsoft Developer Network (MSDN) Web site.


To install the SMTP service


From the Start menu, click Control Panel.


Double-click Add or Remove Programs.


From the left pane, click Add/Remove Windows Components.


From the Components list, click Application Server, and then click Details.


From the Subcomponents of Application Server list, click Internet Information Services (IIS), and then click Details.


From the Subcomponents of Internet Information Services (IIS) list, select the SMTP Service check box.


Click OK.


Click Next. You might be prompted for the Windows Server 2003 family CD or the network install path.


Click Finish.

When you install the SMTP service, a default SMTP server configuration is created with a message store in LocalDrive:\Inetpub\Mailroot.

When setting up the SMTP service for the first time, you can configure global settings for a SMTP virtual server, as well as settings for individual components of the virtual server.


You must be a member of the Administrators group on the local computer to perform the following procedure or procedures. As a security best practice, log on to your computer by using an account that is not in the Administrators group, and then use the runas command to run IIS Manager as an administrator. At a command prompt, type runas /user:Administrative_AccountName "mmc %systemroot%\system32\inetsrv\iis.msc".

To configure global SMTP settings


In IIS Manager, expand the local computer, right-click Default SMTP Virtual Server, and click Properties.


Change the default settings on the property pages as needed. For information about individual settings, click Help.

To configure SMTP virtual server components settings


In IIS Manager, expand the local computer, expand Default SMTP Virtual Server, right-click the component you want to configure, and click Properties.


Change the default settings on the property pages as needed. For information about individual settings, click Help.

Related Information

SMTP Administration

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