POP3 service administration tools

  • Article

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

POP3 service administration tools

The POP3 service provides three methods for local administration and two methods for remote administration.

Local administration

You can administer the POP3 service on the local computer from the Microsoft Management Console (MMC) snap-in, the command line, or the Web Interface for Remote Administration. For more information, see Using Web Interface for Remote Administration.

Remote administration

You can administer the POP3 service on a remote computer from the Microsoft Management Console (MMC) snap-in or the Web Interface for Remote Administration. You can also set up Terminal Services on the remote computer, which would then make the same local computer administration options available. For more information, see Remote administration of POP3 service.

Configuring and managing the POP3 service

The following tables describe the administrative options you can use to configure and manage the POP3 service.

  • General service settings

  • Domain administration options

  • Mailbox administration options

  • Service state settings

General service settings

For information on how to configure these settings, see Set Up the POP3 Service and Change Service Settings.

Service parameter Description

Port

Specifies the port on which the POP3 service monitors for POP3 e-mail clients and responds to connection requests. Do not change the port from its default of 110 unless you have a specific need to do so. You must also inform all users if you are using a nonstandard port because most POP3 e-mail clients configure port 110 as the default for a POP3 connection.

Event logging level

Specifies how much information is stored by the POP3 service in Event Viewer. Logging information is useful for auditing and troubleshooting. The logging levels are:

  • None - No logging.

  • Low - Only critical events are logged.

  • Medium - Critical and warning events are logged.

  • High - Critical, warning, and informational events are logged.

Authentication

Specifies the authentication method used to verify users who connect to the mail server. The POP3 service supports three authentication methods:

  • Local Windows accounts authentication

  • Active Directory integrated authentication

  • Encrypted password file authentication

For more information, see POP3 Service Authentication Methods.

Mailroot

Specifies the directory on the local hard disk where e-mail is stored. For more information, see Mail store.

Sockets

Specifies the number of sockets.

A socket receives the network request from the e-mail client and then handles the transaction. Each time a POP3 e-mail client connects to the mail server, a socket is used. The POP3 service has four configurable settings that control the sockets: maxsockets, minsockets, backlogsockets, and thresholdsockets.

For example, on a system where maxsockets has been set to 20, up to 20 simultaneous connections can be made. If minsockets has been set to 10, when the POP3 service starts, 10 sockets are created immediately. The minsocket value determines how many connection requests the service can respond to on startup, and, based upon the number of sockets to create on startup, how much memory is initially allocated to the service.

New sockets are created based upon the value of thresholdsockets. If thresholdsockets is 5, when the number of available sockets on the server is less than 5, 5 new sockets are created. This increases the total sockets on the system to 15. When the 5 new sockets are filled, 5 additional sockets are created.

This process continues until maxsockets is reached. If maxsockets is 20, when 20 sockets are created and filled, the value of backlogsockets determines how many subsequent connections are accepted, but not responded to. If backlogsockets is 5, the server will accept a total of 25 connections: the 20 connections that fill the available sockets and 5 additional connections that are queued until a socket is available. Connection attempts subsequent to maxsockets + backlogsockets are denied.

Threads

Specifies the number of threads.

A thread is a sequence of program code that is scheduled to run on the processor. A process can have several threads running simultaneously. The operating system coordinates this process by assigning each thread a scheduling priority. With the POP3 service, you can change the number of threads created per processor by configuring the thread count setting. The number of threads per processor multiplied by the number of processors equals the number of simultaneous requests the POP3 service can process.

The number of threads per processor can affect performance when traffic is high. Adding more threads can increase throughput, but adding too many threads will decrease server performance. The default settings are appropriate for most typical environments. For high-load environments, such as dedicated mail servers, the administrator should experiment with the number of threads for best results.

Quotas

Specifies disk quotas that are implemented.

You can implement disk quotas to control the amount of hard disk space allocated for each user's mailbox. Disk quotas are important because they ensure that the server is protected from situations where the mail store might suddenly and rapidly increase in size. For more information, see Configuring disk quotas for the POP3 service.

Domain administration options

For information on how to set these options to manage a domain, see Manage E-mail Domains.

Domain administration Description

Lock/Unlock

Locks or unlocks a domain. Unlocking the domain allows all users in the domain to retrieve their e-mail; locking the domain prevents them from doing so.

When a domain is locked, incoming e-mail for the domain is still received and delivered to the appropriate user directory in the mail store, and outgoing mail is still sent. All users attempting to download mail from the server are denied a connection, however.

While a domain is locked, you can still perform administrative tasks such as deleting a domain. If a user is connected to the mail server when the domain is locked, the mailbox remains unlocked until the user disconnects, after which the mailbox is locked.

Stat

Displays mailbox statistics, including number of messages in a mailbox, lock/unlock status, size of directory, and whether a user is currently connected

List

Lists all mailboxes in the domain.

New domain

Creates a new domain and adds it to the existing POP3 directory structure.

Delete a domain

Deletes an existing domain. If you delete an existing domain, you also delete all mailboxes and stored e-mail for that domain from the mail store.

Mailbox administration options

For information on how to set these options to manage mailboxes, see Manage Mailboxes.

Mailbox administration Description

New mailbox

Creates a new mailbox in an existing domain. To receive e-mail, every user in the domain must have a unique mailbox. Both Active Directory integrated authentication and local Windows accounts authentication support creating an associated user for each mailbox to link POP3 authentication with the existing domain or local computer.

Delete a mailbox

Deletes a mailbox and removes the mailbox from the domain. After a mailbox has been deleted, all e-mail sent to that mailbox is returned to the sender as nondeliverable receipt. When you delete a mailbox, you can specify that the corresponding user account also be deleted.

Lock or unlock a mailbox

Locks or unlocks a mailbox.

When the mailbox is unlocked, the user can connect to the server and retrieve e-mail. When it is locked, the mailbox continues to receive incoming e-mail, which is delivered to the mail store, but the user is not allowed to connect to the server and retrieve e-mail. The administrator can still perform administrative tasks, however, such as deleting a mailbox or changing a mailbox's password.

If a user is connected to the mail server when the mailbox is locked, the mailbox remains unlocked until the user disconnects, after which the mailbox is locked.

Change a mailbox password

Resets the mailbox password. If a user loses or forgets his or her password, you must reset the mailbox password to something new; it is impossible to reveal an existing password.

Service state settings

The POP3 service is a Windows service with full support for Start, Stop, Pause, Resume, and Restart commands. For more information on how to change the POP3 service state, see Change the POP3 service state.

Service state Description

Start

Starts the POP3 service from a stopped or paused state and allows POP3 clients to connect to the server and retrieve e-mail.

Stop

Stops the POP3 service. All current connections are terminated.

Pause

Pauses the POP3 service so that no new connections are accepted. Existing connections are not affected.

Resume

Starts the POP3 service from a paused state to allow POP3 clients to connect to the server and retrieve e-mail.

Restart

Restarts the POP3 service. All current connections are terminated.