Chapter 27

Setting Up a Mail-List Server


CONTENTS


Since the beginning of the Internet, e-mail has been used by millions of people to communicate with each other. The Internet is no longer the simple network that existed a few years ago. It's becoming more complex as new information distribution technologies such as MBone (Multicast Backbone on the Internet) are implemented for tasks such as distributing multicast video streams on the Internet. However, with the advent of all these technologies, Internet e-mail has survived for over a decade and will continue to be a major medium of information exchange among Internet users.

Mail-list servers use Internet e-mail as the principle means of communication. As shown in Figure 27.1, a mail-list server functions by distributing a message sent to it to all its members.

Figure 27.1: When a message is sent to a mail-list server, it is sent to all users who subscribe to the mail list.

There are many advantages to setting up a mail-list server. As you will learn shortly, it is very easy to set up a mail-list server and use it for a variety of tasks. Let us first examine some reasons for setting up a mail-list server and find out how others are using them.

Why Set Up a Mail-List Server?

Unlike other Internet information-distribution services, the amount of work involved in hosting a mail-list server increases with the number of users who are subscribed to various mail lists. Depending on the number of users being serviced by the list server, a fair amount of network resources and time might be needed to maintain it. Before investing valuable resources to maintain a list server, it is worthwhile to explore why you should set up a mail-list server. Since you are reading this chapter, you must probably already have some very good reasons for setting up a mail-list server. Before discussing issues related to setting up and maintaining a list server, the next few sections discuss why you should set up a list server, and they explain, using examples, how a mail-list server can be used to its maximum potential.

How a Mail-List Server Complements a Web Site

Web sites are very effective for distributing information on the Internet. However, Web sites typically require users to visit that particular Web site for information. If the Web site contains valuable information, users who visit it will probably add it to their list of Internet bookmarks. If a user has been on the Internet for a while, this new bookmark will become one of a few hundred bookmarks. Often, when new and interesting information is added to a Web site, there is no way to inform those who will find the new information useful. This is a major drawback associated with solely relying on a Web site to distribute information. A mail-list server can be used to effectively nullify this drawback, with which virtually all Web sites are plagued.

A list server complements a Web site by providing the content publisher another way of distributing information and inviting users to visit the Web site for more detailed information. For example, you might want to create a newsletter and e-mail it to an interested group of people via a mail list to keep them informed of latest developments related to your organization and summarize new additions that were made to its Web site. If a user is interested in a particular summary, the user can then visit the corporate Web site for more detailed information. Refer to Figure 27.2 for an example of how a newsletter can be used to attract users to a Web site. Figure 27.2 contains part of the Advanced Systems User Group's (ASUG) monthly electronic newsletter. ASUG is a Windows NT user group in the Washington D.C. area, and as you can see, the monthly newsletter is used to invite its members to visit the ASUG Web site for more information. A mail-list server complements a Web site because it can be used to attract visitors.

Figure 27.2: A newsletter distributed via a mail list can be used to invite list members to visit a Web site for more information.

Benefits of Setting Up a Mail-List Server

A mail-list server can be used for a variety of tasks. Many organizations use mail-list servers to keep customers informed of new developments and host public discussion forums on the Internet. For example, at the time of this writing, a Yahoo! search on the search string "mail list" found 845 matches. As you can see in Figure 27.3, these matches are for Internet mail lists that discuss various topics.

Figure 27.3: A Yahoo! search alone yields about 850 different topics covered by various Internet mail lists.

The large number of topics listed in Figure 27.3 proves the usefulness of mail-list servers. Listed next are various benefits of setting up a mail-list server. Some of these benefits will be discussed in greater detail shortly.

Obtain User Feedback

The ability to obtain user feedback is a major advantage in setting up a mail-list server. Although e-mail can be used for the same purpose, it does not give users the chance to discuss various problems they are having. For example, when a user has a problem with a certain product or service, another mail-list member might be able to help this user by providing a possible solution or work-around to solve the problem. This helps cut down support costs and also provides a way to obtain user feedback.

Discuss a Topic in Detail

Mail lists are well suited for discussing a topic in detail. Because one topic is discussed in detail, such lists usually attract various experts in the field being discussed, and they become a rich source of information for many people. An example of such a list is shown in Figure 27.4.

Figure 27.4: The firewall mail list is an example of a mail list set up to discuss a topic in detail.

Keep Users Informed

Since the beginning of the Internet, e-mail has been used to keep users informed of new developments. Although it is not necessary to set up a mail list to inform users of new developments, not setting up a mail-list server can turn into a lot of work if you are dealing with a relatively large user database. For example, after requesting to be kept informed of new developments, a user might change his or her mind. In a similar manner, a new user might want to be added to the list so she will be kept informed of new developments. This can create a lot of work; new users have to be manually added to a list, and various users need to be manually deleted from the list. In addition to this, the latest list might not always be available to everyone, and more than one person might need to contact the group of people in the list. Because everything is done manually, when a change is made, it needs to be propagated to everyone else who might need to contact people in the list. This can be unnecessarily time-consuming. On the other hand, a mail list can be set up to automate this process. Users will then be able to join and leave the list by themselves. By using a special password, those who are authorized to post to the list will then be able to send messages to the list server. Refer to Figure 27.5 for an example of a mail list set up to keep users informed of new developments.

Figure 27.5: The Internet Shopper NTMail update mail list is an example of a mail list set up to inform customers of new products.

Discuss Various Hobbies and Interests

Mail lists are also effective for creating discussion forums on the Internet for people to discuss various hobbies and interests. Although such forums are not directly beneficial to an organization business-wise, a mail list can be set up to discuss a special interest or hobby as a way of giving something back to the Internet and improving your company's public image. The Yacht mail list shown in Figure 27.6 is an example of a mail list set up to discuss a special interest.

Figure 27.6: The Yacht mail list.

Distribute an Electronic Publication

As shown in Figure 27.7, an electronic publication can be easily distributed to many users using a mail-list server. Again, an advantage of using a mail-list server instead of a mail server alone is the fact that when a mail-list server is used, list members can join and leave the list whenever they want to.

Figure 27.7: The News of the Weird Mailing List is a mail list that has been set up to distribute an electronic publication.

Provide Technical Support

Mail-list servers are well suited for providing technical support to users. Although regular e-mail can be used to do this, it is not very efficient. If one user encounters a problem, it is likely that others will encounter the same problem. When a mail-list server is used, all users who are subscribed to the list server will find out how to deal with many potential problems. This can cut down on the time and resources needed to provide technical support. Furthermore, mail lists also enable users to help each other rather than wait for a technical support person to respond to a message. This does not mean that users should be left to help each other; it can easily lead into a public relations nightmare. It just means that a user having a problem will often find out how to solve the problem in more ways than one.

Public Service

An example of a mail list used to provide a public service is shown in Figure 27.8. The Webserver-NT mail list has been set up by Process Software to discuss various issues related to publishing information on the Internet with Windows NT. Although Process Software does not directly benefit from this mail list, it's a good way to inform Windows NT users about Process Software's Web publishing applications. Setting up a mail list to discuss a product or service you are marketing is often mutually beneficial for you and your users.

Figure 27.8: The Webserver-NT mail list discusses various issues related to developing Web sites on the Internet with Windows NT.

Mail-List Server Requirements and Tips

Listed next are a few tips that will help you host an efficient and user-friendly mail-list server.

Bandwidth Requirements

It is not desirable to host a high-volume mail list on a POTS link to the Internet. This can virtually take away all your limited bandwidth and render your Internet connection worthless. However, if your mail list is going to consist of only a few dozen users, you will be able to make do with a POTS link as long as list members do not send extremely long messages or binary files to your list. On the other hand, if you intend to set up a mail list that is expected to have a few hundred or thousand users, at the very least make sure you have an ISDN line to the Internet.

Hardware Requirements

As far as system resources are concerned, by far the most limiting factor is the bandwidth of your Internet connection. A list server is not very hardware-intensive. A computer running Windows NT with a 486/DX2/66 or better processor will often be sufficient. However, depending on the amount of list members and other applications being run at the same time, additional RAM or processing power may be required. When running a mail-list server along with other network services, a minimum of 24 MB of RAM for NT Workstation and 32 MB of RAM for NT Server is recommended.

Keep Messages Short

You should not use a newsletter distributed via a mail list to list everything that happened in your organization in the last month-from the new lunch menu to a groundbreaking product or service that was just made public. Chances are that your list members already receive dozens of e-mail messages a day. Long messages distract recipients by shifting away their attention from the contents of the message to its length. (Ever read an e-mail message wondering when it will be over?) On the other hand, Web sites are there to provide detailed information. Use your Web site to publish detailed information, keep newsletters short and concise, and include URLs at your Web site for more information.

Things to Watch Out for

There are a few things you should watch out for when hosting a mail list. Unlike other types of information-distribution systems, maintaining a mail list is a rather sensitive job. Messages sent to a mail list are distributed to all its list members; a mishap can easily make quite a few people unhappy. Listed next are a few things you should watch out for when putting a mail-list server to use.

Binary Files

You should do everything you can to discourage users from sending binary files to a list server. Although files can be attached to an e-mail message when they are sent, the work involved in dealing with such messages literally multiplies when attachments are involved. For example, if a list has 200 members and a 2 KB file is sent to the list with a 200 KB file attached, over 40 megabytes of data needs to be transmitted by your list server! This is not good. If not for the attachment, in order to distribute the message to the list, only 400 KB of data needs to be transmitted. As you can imagine, even if a few people send e-mail messages to a list server with attachments, things can get rather nasty. This situation can cascade into a nightmare if some of these messages get sent back to the mail-list server and get redistributed. Such an incident can easily add several dozen unhappy e-mail messages to your inbox. It is a good idea to make a note of this in the "welcome letter" that is sent to new members as soon as they are subscribed to a mail list. You might want to make the second line of the welcome letter read something similar to: "Please do not send e-mail messages with attachments to this list for any reason." In order to enforce this rule, your list server should let you specify the largest message size it will accept. Messages that are larger than the size specified will then be ignored and not circulated.

Subscribing Users Without Their Knowledge

After setting up a mail-list server, it might be tempting for you to add every person that e-mails you in search of information to a mail list. Although in principle it is a good idea, in reality it can turn into a public relations nightmare. For example, after a few dozen users are subscribed to such a mail list and start exchanging mail messages to and from the list, some are going to wonder how and from where they are getting all these messages. These users might tolerate the e-mail for a while- until a user decides to ask a very simple question on the list. When people intentionally subscribe to a list, they more or less expect this kind of e-mail. However, when users are subscribed to a list without their knowledge and start receiving trivial questions like how to unzip a .zip file, they are less tolerant. Therefore, you should avoid subscribing users to a list without their knowledge. If you are still not convinced, I am sure Figure 27.9 will convince you of consequences associated with subscribing users to a list without their permission. What's shown in Figure 27.9 is a number of e-mail messages that resulted from a number of users being automatically subscribed to a list. Just as soon as someone asked a trivial question, several users began sending e-mail to the list asking them to be taken off the list.

Figure 27.9: Subscribing users to a mail list without their permission is not a verty good idea and can result in not-so-desirable consequences.

The purpose of Figure 27.9 is not to downgrade the company that automatically subscribed a few users to their mail list. It is merely to show consequences of not asking permission to do so. Incidentally, the company that hosted the mail list in Figure 27.9 makes a wonderful Web-publishing tool that was covered in an earlier chapter.

If you add users to a mail list without their knowledge, make sure it is a very low-volume, announcement only mail list that's set up so that its members can't post messages to the list. Such a list can be used to distribute information about new developments, products, and services.

Troublesome Users

Just like the real world, the Internet has its own share of troublesome people who wreak havoc by disrupting the normal flow of things. Because mail lists usually discuss various issues that might challenge ideals and beliefs of some people, it's very easy for someone to start a flame war. A flame is generally a bunch of messages that are full of personal insults and very little substance. They often start innocently but can get quite nasty. Flame wars are undesirable. They waste system resources and distract users from more important things that are worth discussing by shifting the focus from the topic being discussed to various personal beliefs and viewpoints. It is important to keep flame wars under control. If a disruptive user is discovered, it is generally desirable to politely e-mail the user and ask the user to stop what he or she is doing. It's not a very good idea to do this publicly. If you still have problems after a number of warnings, you need to take administrative action. In order to do this, you need to have a mail-list server that has special provisions for dealing with such users. The list-server program covered in this chapter has such a provision.

Windows NT Compatible Mail-List Servers

Several mail-list servers are available for Windows NT. URLs of several mail servers that run on Windows NT are listed next. Out of these servers, the remainder of this chapter focuses on installation and configuration issues related to NTList. NTList is a very feature-rich and easy-to-use mail-list server. For your convenience, a copy of NTList is included in the CD-ROM that accompanies the book.

L-Soft International Inc. LISTSERV:
http://www.lsoft.com/
EMWAC Internet Mail Server:
http://emwac.ed.ac.uk/html/internet_toolchest/ims/ims.htm
NTList Mail-List Server:
http://www.net-shopper.co.uk/software/ntmail/ntlist.htm

Installing Mail-List Server Software

NTList is integrated with NTMail, a Simple Mail Transport Protocol (SMTP)/Post Office Protocol (POP) mail server for Windows NT. NTList makes efficient use of system resources by utilizing the capabilities of NTMail to send list-server messages. Although NTMail is included in the CD-ROM, you may want to download the latest version of NTMail from the Internet Shopper World Wide Web site.

URL
The latest version of NTMail can be obtained from the Internet Shopper Web site:
http://www.net-shopper.co.uk/software/ntmail/index.htm

Technical Note
Requests for Comments (RFCs) are working notes of the Internet research and development community. NTMail is based on several RFCs published by the Internet Engineering Task Force. These RFCs are RFC 821, RFC 822, RFC 974, RFC 1035, RFC 1123, RFC 1521, and RFC 1725.
More information about these RFCs can be obtained from
http://www.internic.net/ds/rfc-index.html

In order to use the functionality of NTList, NTMail has to be installed first.

Installing NTMail

Installing NTMail is very straightforward. First, you need to either download the latest version of NTMail from the URL given earlier or locate the NTMail distribution file in the CD-ROM. Copy the NTMail distribution file to a temporary directory and decompress the .zip file. It is recommended that you use a 32-bit file-decompressing utility such as WinZip to ensure any long filenames in the archive are preserved. Also, be sure to use appropriate switches of the file-decompressing utility to make sure that directory path names are preserved. After the NTMail distribution file is decompressed, follow subsequent directions to install NTMail/NTList on your system.

Caution
Before installing NTMail, make sure other SMTP and POP3 servers, such as the free EMWAC mail server, are stopped. Failure to do so can complicate the installation process when NTMail attempts to bind with a TCP/IP port on your system.

Execute setup.exe to begin the installation process. You will be presented with a dialog box similar to the one shown in Figure 27.10. In this dialog box, you need to provide NTMail with a registration key, the directory you wish NTMail to be installed in, and your domain name. If you intend to use NTMail/NTList, you should register it and obtain a permanent key that does not expire. If not, at the end of each month, you will have to obtain a temporary key from the NTMail distribution site. You will be pleased to know that the developer of NTMail was kind enough to let the readers of this book have an initial key. Rather than visit the Internet Shopper Web site to obtain a key, you can type demo to install and use NTMail immediately. Please note that this key will expire at the end of next month, and you will either need to obtain a new key or register your copy of NTMail/NTList after the trial period.

Figure 27.10: The NTMail setup dialog box is used by NTMail to gather critical installation information.

After typing the NTMail key, type the directory you wish NTMail to be installed in and your Internet domain name. Do not select a disk partition that barely has enough room for NTMail. When you start using NTMail for e-mail and NTList to host discussion lists, messages can take up a lot more disk space than NTMail itself. After typing your domain name, press OK to continue installing NTMail; the following Windows NT services will be added and started by the NTMail installation program:

In addition to this, as shown in Figure 27.11, three new icons will also be added to Control Panel:

Figure 27.11: The NTMail installation program adds three new icons to Control Panel.

NTMail is now installed and ready for use. The following section demonstrates how to create NTMail user accounts.

Creating User Accounts

After NTMail is set up, it is recommended that you at least create an account for yourself and another account for the Web administrator of your system (usually called a Webmaster). In order to add users to NTMail, execute the NT Users application in Control Panel. You will then see a dialog box similar to the one shown in Figure 27.12.

Figure 27.12: New users can be added to NTMail by executing the NT Users application in Control Panel.

Click the Add button to add a new user. As shown in Figure 27.13, you will then be asked for the type of new user you wish to add. Select User | Holiday Message and press OK to continue.

Figure 27.13: Various types of users can be added to NTMail.

You will then be presented with a dialog box similar to the one shown in Figure 27.14. To create a user account for the Web administrator, type webmaster in the space provided for Username. If the NTMail username just typed in is also a Windows NT username, NTMail gives the option of either using the password in the NT user database or a new NTMail password. For example, if webmaster was also an NT user, webmaster can be added to use the NT user database password, by clicking on Add. The same account can also be added to use a different password by clicking on the password checkbox, typing a password, and clicking Add. Additional aliases for a user can be specified by typing them in the space provided for Aliases.

Figure 27.14: The Users tab can be used to add new users.

After webmaster is added as an NTMail user, as shown in Figure 27.15, the user Accounts List will be updated to reflect the new user who was added.

Figure 27.15: The Accounts List tab lists all NTMail users.

In order to save the changes you made, click Apply. When you exit the NTMail Users application, you will see a dialog box similar to the one shown in Figure 27.16. Answer Yes to this dialog box, and the changes you made will be updated to relevant NTMail services.

Figure 27.16: NTMail provides an option to update new configuration information to NTMail services when exiting the NTMail Users application.

Using NTMail

At this point, NTMail is fully functional. NTMail users can now receive e-mail provided that the NT machine is properly connected to the Internet. You can test NTMail by sending a message to NTMailUser@your.Internet.address. Mail messages sent to NTMail users can be read using a number of mail clients such as Pegasus Mail and Eudora. If you are looking for a feature-rich, free mail client, use either Microsoft Exchange Client that comes with NT 4.0 or Pegasus Mail.

URL
Pegasus Mail can be obtained free of charge from
http://www.cuslm.ca/pegasus/

URL
Eudora is a Windows NT-compatible mail client. It comes in two versions. The "light" version is freeware but has limited capabilities. The "pro" version is more feature rich. Eudora can be obtained from
http://www.qualcomm.com/ProdTech/quest/

Monitoring Mail-Server Statistics

NTMail statistics can be obtained and monitored using Performance Monitor. In order to monitor NTMail statistics, invoke Performance Monitor and select Edit | Add To Chart. This will bring up an Add to Chart dialog box similar to the dialog box in Figure 27.17. This dialog box can be used to add various NTMail performance counters to Performance Monitor.

Figure 27.17: Various NTMail performance counters can be added to Performance Monitor's chart.

By adding various NTMail counters to the chart, you can monitor various statistics as shown in Figure 27.18.

Figure 27.18: NTMail performance counters can be monitored using Performance Monitor.

In addition to monitoring counters, by adding NTMail counters to "alerts" it is even possible to configure various programs to run when certain conditions are met. This is a powerful feature. For example, under the POP object, there is a counter by the name of Failed Authorizations/Sec. A high Failed Authorizations/Sec count is a harbinger of a possible system-security breach. Using Performance Monitor, you can set up a program to be executed when such a counter is suspiciously high. It is a good idea to invest in an application that can send text messages to alphanumeric pages. By using such an application along with Performance Monitor, even if you are fast asleep at 3 in the morning, you will know if someone is trying to break into one of your mail servers!

Creating and Managing Mail Lists

Now that NTMail is all set up, you can set up e-mail lists by configuring NTList. NTList is configured using the NTList application in Control Panel. When the NTList application is first invoked, it will look similar to Figure 27.19. By default, no mail lists are present.

Figure 27.19: When the NTList configuration application is first invoked, it does not contain any e-mail lists.

NTMail uses list managers to manage various mail lists by helping group various mail-list topics into mail-list categories. For example, a list manager called "NT-Request" can be created to manage Windows NT-related discussion lists. As you can see, breaking down various mail lists into categories and creating a list manager for each category helps mail lists to be managed in a logical manner.

For the purpose of this example, you will be shown how to create an e-mail list to discuss Web-publishing issues related to Windows NT. This mail list will be called WWW-NT. As mentioned earlier, before creating an e-mail list, a list manager has to be created. Because the WWW-NT mail list discusses various issues related to using Windows NT, the list manager can be called NT-Request. In order to create this list, first create a list manager by the name of NT-Request. After highlighting the list manager just created, create a Managed List by the name of WWW-NT. The NTList configuration application will now look similar to Figure 27.20. A mail list can be set up very easily by following the directions. In order to make the WWW-NT mail list operational, it is required that you update the NTMail service. This can be done by exiting the NTList configuration application and answering Yes to a dialog box similar to the one shown in Figure 27.16.

Figure 27.20: Mail lists are created by creating a managed list under a list manager.

Note
NTList services have to be restarted in order for any changes to take effect.

At this time, if a message similar to the one shown in Figure 27.21 is sent to the mail list, the sender will receive a message similar to the one shown in Figure 27.22 confirming the list subscription was a success. In addition to this, another message will be sent to the list subscriber detailing various list-server commands. These commands will be covered shortly.

Figure 27.21: Message sent to list server to subscribe to the WWW-NT mail list.

Figure 27.22: Message sent by NTList to confirm the addition of a new user to the WWW-NT mail list.

Note
The purpose of this chapter is not to comprehensively cover all aspects of configuring NTList and NTMail. Instead, it is to provide you an overview of various benefits associated with setting up a mail-list server and a brief overview of how NTMail and NTList can be used to set up an Internet mail list. Please refer to NTMail and NTList documentation included in the CD-ROM for additional configuration information.

List-Server Commands

All list-server commands are handled by list managers. Users can join and leave a mail list as well as perform a few other tasks by sending commands to the list manager. Unlike users, list moderators can send administrative commands to the list manager using a password. Listed next are various list server commands supported by NTList.

JOIN and SUBSCRIBE

Users can join a mail list by sending either a JOIN or SUBSCRIBE message to the list manager. For example, if the user whose e-mail address is carina@CreativeLink.com wants to join the WWW-NT mail list created earlier, she'd have to send the following message to the list manager (NT-Request).

JOIN WWW-NT carina@CreativeLink.com
password <mail list password if set>

or

SUBSCRIBE WWW-NT carina@CreativeLink.com
password <mail list password if set>

DIGEST

Some users prefer to receive one large e-mail message from a mail list at the end of the day as opposed to many small e-mail messages at all times of the day. This option can be set by using the DIGEST command as outlined next.

DIGEST <list name> <e-mail address>
password <mail list password if set>

In order for this feature to work, the list should have the Log Messages checkbox enabled in the NTList configuration application, as shown in Figure 27.23. If a digest user wants to receive messages in real time once again, that user has to send a JOIN message to the list manager, as outlined earlier.

Figure 27.23: In order for the mail-list digest feature to work, the Log Messages checkbox has to be checked.

LEAVE and UNSUBSCRIBE

List members can leave the list by sending the following message to the list manager:

LEAVE <list name> <user's e-mail address>
password <mail list password if set>

or

UNSUBSCRIBE <list name> <user's e-mail address>
password <mail list password if set>

Help

If an invalid command or list name is sent to the list manager, the list manager's help file will be sent to the user. This message can be edited as shown in Figure 27.24. The same help message is sent to new subscribers.

Figure 27.24: The Help Msg tab of the NTList configuration application can be used to edit the help message of a mail list.

LIST

If it is allowed, the LIST command can be used by users to obtain a list of users who subscribe to the mail list. This list can be sorted by domain name or alphabetical order. The syntax of the LIST command is as follows:

LIST <list name> <sort method>

where <sort method> can be ALPHA or DOMAIN.

PASSWORD

This command is used along with other commands that require a password. In addition to administrative commands discussed shortly, various list commands can be restricted by assigning a password using various Allow tabs (Post Allow, List Allow, Get Allow) of the NTList configuration application.

Administrative Commands

Administrative commands can be used to obtain various information about the status of the list server and also perform administrative tasks. In order for administrative commands to function,
a registry key by the name of ListServerPassword has to be created, as shown in Figure 27.25.

Figure 27.25: A registry key (ListServerPassword) has to be added before administrative commands can be sent to a mail-list manager.

Registry
The registry key ListServerPassword has to be created in order for mail-list server administrative commands to be interpreted by the list server.
  Key Name:          SOFTWARE\InternetShopper\Mail\Parameters
  Value Name:      ListServerPassword
  Type:            REG_SZ
  Data:            <Password of List>

The following administrative commands are supported by NTList:

RESEND

Causes the list manager to send a digest of the list to all members who have requested digest messages.

RESEND <listname> [day month year]
PASSWORD <list password>

Example:

RESEND WWW-NT 18 03 1996
PASSWORD ListServerPassword

VERIFY

The VERIFY command is used to obtain a list of invalid user e-mail addresses. NTList compiles this report by contacting the mail server of each list subscriber and validating their e-mail address. The syntax of the VERIFY command is as follows:

VERIFY <list name>
PASSWORD <ListServerPassword>

Summary

Mail lists are different from other Internet information-distribution applications discussed earlier because they are highly interactive. Managing a mail list may involve some extra effort to keep the list functioning smoothly. However, when used properly, there are many advantages in setting up a mail-list server. By referring users to a Web site for more information via a newsletter, a mail-list server can be used to complement information distributed by a Web site. Windows NT mail-list servers are extremely easy to set up and administer. As shown earlier, the mail-list server included in the CD-ROM can be set up and put to use in a matter of minutes. By using a mail-list server to host discussion forums, you will be able to take advantage of various unique benefits offered by mail lists and make users more productive.

What's Next?

The next chapter discusses how to set up a domain name server under Windows NT. Whenever you connect to an Internet host-for example, www.microsoft.com-a domain name server translates www.microsoft.com into an Internet Protocol address such as 198.105.232.4 before the connection is made,. This process is crucial for locating and connecting to various Internet hosts. The following chapter demonstrates how to set up and configure a domain name server.