RFC 821 - Simple Mail Transfer Protocol
RFC 822 - Standard for the Format of ARPA Internet Text Messages
RFC 1521 - MIME Part One: Mechanisms for Specifying and Describing
RFC 1522 - MIME Part Two: Message Header Extensions for Non-ASCII Text
RFC 1855 - Netiquette Guidelines
RFC 1939 - Post Office Protocol - Version 3 (POP3)
RFC 2142 - Mailbox Names for Common Services, Roles, and Functions

Additional information can be found on web pages dedicated to NTP servies:

The Internet Mail Consortium
Sendmail Home Page

The Internet provides thousands of discussion groups via e-mail by allowing users to place themselves on electronic mailing lists.

These mailing lists are maintained by software (e.g. LISTSERV(R), LISTPROC, Majordomo , etc.). The software automatically distributes an e-mail message from one member of a list to all other members on that list. Thousands of lists in the form of digests, electronic journals, discussion groups and the like are available.

When you subscribe to a list, your name and e-mail address is automatically added to the list. You will receive a standard letter of welcome (via e-mail) telling you about the list. From that time on, you will receive all mail (postings) sent to the list by its members. You may follow the discussions or join in on them. If you respond, you can send your response to the list (in which case, all members of the list will receive it), or to an individual on the list. You can signoff (unsubscribe) from a list at any time. You can also get a listing of all the members of a list and their e-mail addresses.

In working with a mailing list, there is one thing that you must keep in mind. Every list has two addresses. The first is the "list manager" address. This is the address you send commands to (eg. subscribe or unsubscribe). Only the software sees these messages. The other address is the "list" address. This is where you send the messages that you want everyone on the list to recieve.

CataList the official catalog of LISTSERV lists
Rob Kabacoff's compilation of E-Mail Discussion Groups
IFLA Internet Mailing Lists Guides and Resources
Publicly Accessible Mailing Lists

Spam is flooding the Internet with many copies of the same message, in an attempt to force the message on people who would not otherwise choose to receive it. Most spam is commercial advertising, often for dubious products, get-rich-quick schemes, or quasi-legal services. Spam costs the sender very little to send -- most of the costs are paid for by the recipient or the carriers rather than by the sender.

The official Hormel Foods SPAM website
Network Abuse Clearinghouse
Fight Spam on the Internet
Spamcop.Net
Coalition Against Unsolicited Commercial Email (CAUCE)
Stopping Spam and Trojan Horses with BSD by Brett Glass

Mail Abuse Prevention System (MAPS)
MAPS Realtime Blackhole List (RBL)
MAPS Dial-up User List (DUL)
MAPS Relay Spam Stopper (RSS)
Open Relay Blackhole Zones (ORBZ)

use	zone	description	2002 hits	2003 hits	2004 hits
	relays.osirusoft.com	combined list from osirusoft.com	~18.2%	~3.4%	down
	dialups.osirusoft.com	dynamic IP pools with potential for direct-to-MX spam	~0.5%	~0.0%	down
	spamsites.relays.osirusoft.com	spamware sites from spamsites.org	~0.1%	~0.0%	down
	sbl-xbl.spamhaus.org	Direct UBE sources, verified spam services and ROKSO spammers from SBL and Illegal 3rd party exploits, including proxies, worms and trojan exploits from XBL	~	~	~39.2
	sbl.spamhaus.org	Direct UBE sources, verified spam services and ROKSO spammers	~3.7%	~0.0%	~5.9%
	xbl.spamhaus.org	Illegal 3rd party exploits, including proxies, worms and trojan exploits	~	~	~34.1%
	spews.relays.osirusoft.com	spam supporting sites from spews.org	~5.7%	~1.6%	down
	outputs.relays.osirusoft.com	more aggressive filtering of outputs of multi-stage relays	~	~	down
	bl.spamcop.net	This list contains IP addresses which have been reported to SpamCop as carriers of SUBE, whether directly or indirectly. Some of these reports come from 'spamtraps' (email addresses used strictly to receive spam).	~	~	~17.5%
	inputs.orbz.org	single-stage or input relays	~	down	down
	outputs.orbz.org	more aggressive filtering of outputs of multi-stage relays	~	down	down
	list.dsbl.org	single-stage relays, open proxies allowing CONNECT, insecure web formmail	~5.6%	~18.3%	~34.0%
	dnsbl.njabl.org	127.0.0.2 - open relays 127.0.0.3 - dial-up/dynamic IP ranges 127.0.0.4 - Spam Sources 127.0.0.5 - Multi-stage open relays 127.0.0.8 - Systems with insecure formmail.cgi or similar CGI scripts 127.0.0.9 - Open proxy servers	~	~	~23.8%
	relays.ordb.org	relays	~3.3%	~1.7%	~0.8%
	blackholes.mail-abuse.org	generally unrepentant spammers	~	sub	sub
	dialups.mail-abuse.org	dialup and other dynamically assigned addresses	~	sub	sub
	relays.mail-abuse.org	single-stage relays with observed spam	~	sub	sub
	relays.visi.com	single-stage relays with observed spam	~2.4%	~3.2%	~3.7%

  Netscape Navigator Gold 3.0 is a suite of internet utilities from
Netscape Communications Company including a browser, an email client, and
a news client.

  In Netscape, select [Options] and then [Mail and News Preferences...].

  Select the [Identity] tab.  Enter Your name (John Smith) and your Email
Address (smith@rxn.com).  The Your Organization (RXN) and Signature File
fields are optional.

  Select the [Servers] tab.

  Under Outgoing Mail, enter the SMTP Server (chemica.rxn.com).

  Under Incoming Mail, select POP3, enter the Server (chemica.rxn.com),
and your User Name (smith).  For After Delivery, select Remove from
server.  You may also select here the frequency with which Netscape will
check for new mail while it is online.  Point the Mail Directory to the
location on your system where you would like messages stored.

  Under News, enter the News (NNTP) Server (news.rxn.com) and point the
News Directory to the location on your system where you would like
messages stored.

  You can further configure how you work with your mail by making
selections under the [Appearance], [Compose], and [Organization] tabs.

  When you have completed the entries, select [OK] in the Preferences box
to save your configuration.

  Select [Window], then [Netscape Mail], to access your email client.

  Netscape Communicator 4.5 is a suite of internet utilities from Netscape
Communications Company including the Navigator browser and the Messenger
email client.

  In Netscape Communicator 4.5, select [Edit], then [Preferences...], and
then expand the [Mail & Newsgroups] tab.

  Select the [Identity] tab.  Enter Your name (John Smith), your Email
address (smith@rxn.com), and your Reply-to address (smith@rxn.com).  The
remaining fields are optional.  Screen shot.

  Select the [Mail Servers] tab.  Under Incoming Mail Servers, Add or Edit
in the Server Name (chemica.rxn.com), Server Type (POP3 Server), and User
Name (smith).  Screen shot.

  Under Outgoing Mail Server enter Outgoing mail (SMTP) server
(chemica.rxn.com) and Outgoing mail server user name (smith).  Screen shot.

  When you have completed the entries, select [OK] in the Preferences box
to save your configuration.

  Select [Communicator], then [Messenger], to access your email client.

  MS Outlook is a commercial email client from MicroSoft.

  In MS IE, select [View], then [Internet Options...], then select the
[Programs] tab.  Next to the Mail label, select MS Outlook. Save your
changes.  Note, if you are interested in accessing usenet newsgroups, you
may wish to consider MS Outlook Express.

  Then configure Outlook with your user name and address as follows...

  Double-click on the MS Outlook icon.

  Select the [Tools] pull-down menu.

  Select [Services...].

  Select the [Services] tab.

  Verify that the Internet Mail information service appears in the profile
window.  If not, use the [Add...] button to load this service.

  Once the Internet Mail service appears in the profile window, highlight
it, and select the [Properties] button.

  Select the [General] tab in the Internet Mail window that appears.

  For Full Name, enter your name as you would like it to appear in your
message From field.  For example:  John Smith

  For E-mail Address, enter the email address assigned to you by RXN
Communications.  For example:  smith@rxn.com

  For Internet Mail Server, enter:  rxn.com

  For Account Name, specify the POP account name provided to you by RXN
Communications.  For example:  smith

  For Password, specify the password provided to you by RXN
Communications.  Remember that your account name and password are case
sensitive.

  Select [Apply], and then [OK] to exit the Internet Mail window.

  Select [Apply], and then [OK] to exit the Services window.

  You may wish to review the other configuration choices in the [Tools]
pull-down menu under the [Options...] selection.  Choose them to suit your
needs.

  Select [Ok].

  Select [File], then [Exit].

We will use, in this outline, an example user named John Smith with an RXN mail account name of smith@rxn.com and a dialup PPP account name of Psmith. You will need to substitute your own account names.

  MS Outlook Express is the mail interface distributed with IE 4.0.

  In MS IE, select [View], then [Internet Options...], then select the
[Programs] tab.  Next to the Mail and News labels, select Outlook Express.
Save your changes.

  Then configure Outlook Express with your user name and address as
follows...

  Double-click on the MS Outlook Express icon.

  Select the [Tools] pull-down menu.

  Select [Accounts...].

  Select the [Mail] tab.

  Select the [Add>] button.  Note that multiple email accounts can be
configured here.

  Select [Mail...].  This will load the MS Internet Connection Wizard
which will prompt you for configuration information.  Note that the
Internet Connection Wizard is an adaptive configuration utility that will
change its prompts depending on the configuration of the system it is
running on.  The following prompt sequence is the most common.  If a
screen appears that is not mentioned in these instructions, select
[Next>].  If you do not have a screen mentioned in these instructions,
skip down to the next sentence.

  For Display Name: enter your name as you would like it to appear in your
message From field.  For example:  John Smith

  Select [Next>].

  For E-mail Address: enter the email address assigned to you by RXN
Communications.  For example:  smith@rxn.com

  Select [Next>].

  Specify that your incoming mail server is a POP3 server.
  For incoming mail (POP3) server specify:  rxn.com
  For outgoing mail (SMTP) server specify:  rxn.com

  Select [Next>].

  For your internet mail login, specify the POP account name provided to
you by RXN Communications.  For example:  smith 

  Specify the password provided to you by RXN Communications.  Remember
that your account name and password are case sensitive.

  Select [Next>].

  For your Internet Account Friendly Name, specify:  RXN Communications

  Select [Next>].

  Depending upon the MS Outlook Express version, you may need to highlight
the Account and select Properties to access the following settings.
 
  For Connection Type, specify that you will:  Connect using my phone
line.  NOTE:  If you are picking up RXN email over another data link,
select the Connections tab of the properties window, check the Always
connect to this account using box, and then select the other data link
from the pull-down menu.

  Select [Next>].

  For your Dialup Connection, specify that you will use an existing
connection, and select the RXN Communications connection that you have
previously configured.

  Select [Next>].

  Select [Finish].

  The RXN Communications mail account you have just configured should now
appear under the Mail tab of the Internet Accounts window.  Highlight the
RXN Communications account and select the [Set as Default] button.

  Select [Close].

  Select the [Tools] pull-down menu.

  Select [Options...].

  Select the [General] tab.

  Check the box that indicates that you would like to make Outlook Express
your default email program.

  You may wish to review the other configuration choices in the Options
window, selecting them to suit your needs.

  Select [Ok].

  Select [File], then [Exit].

If you are using one of the MS Windows 95/98 email clients, like MS Outlook, you can configure your system to send MIME encoded messages as follows:

  Click [Start], then [Settings], then [Control Panel].  Then open [Mail
and FAX].  

  Under the [Services] tab, select [Internet Mail], and then [Properties].  

  Under the [General] tab, select the [Message Format] button and confirm
that the "Use MIME when sending messages" box is checked.

Tools for secure web email interfaces include:

• Endymion Corporation's Mailman
  • FAQ for MailMan version 3.0
  • mmstdod.tar.gz
• AtDot's Webmail
  
  • FAQ for AtDot E-Mail Services
  • README for AtDot-2.0.1.tar.gz
  • README for AtDot-2.91.1.tar.gz
  • doc/conffile for AtDot-2.91.1.tar.gz
  • 18 nov 1999 chat with sparky
  • AtDot-2.0.1.tar.gz
  • AtDot-2.91.1.tar.gz
• The Horde Project's IMP
  

Era Eriksson's Procmail Mini-FAQ
Jari Aalto's Procmail Tips
Jari Aalto's Pointers to Procmail Resources

Additional information can be found on the Procmail web site:

Procmail Home Page

If you have at least MacOS 7.0, download the Eudora 3.1.3 client and the Eudora 3.1 manual, and then step through the following instructions...

================================
EUDORA LIGHT FOR MACINTOSH 3.1.3
================================

This is version 3.1.3 of Eudora Light for Macintosh. This README provides
information on the following topics:

*  Minimum Requirements
*  Drag and Drop Requirements
*  Installation
*  New Features and Changes in 3.1.3
*  License and Legal Information

======================
MINIMUM REQUIREMENTS
======================

To use Eudora Light for Macintosh, you must have the following:

*  A Macintosh Plus or later model.
*  Macintosh System 7.0 or later.
*  A mail account with an Internet service provider or an Internet-style
                network account.
*  Access to your mail account via a modem or Internet-style network
    connection.

============================
DRAG AND DROP REQUIREMENTS
============================

If you do not have Macintosh® Drag and Drop running on your Macintosh,
certain features may be disabled. Macintosh Drag and Drop is included in
System 7.5 and System 7 Pro, but is not in earlier versions of System 7.

Macintosh Drag and Drop requires that Finder 7.1.3 or newer is running for
the Drag and Drop extensions to work properly. Installing the Drag and
Drop extensions with an older Finder has been shown to cause strange
behavior, and is not recommended.

If you are running a system version with a Finder that is older than
7.1.3, you will be able to drag and drop within the Eudora application.
However, you will not be able to drag between Eudora and other running
applications.


==============
INSTALLATION
==============

You can install this version of Eudora Light over an earlier version of
Eudora Light. Just follow the instructions below, and when you open the
new version of Eudora, your Settings, mailboxes, etc. will be updated for
the new version.

To install Eudora Light, do the following:

1.   Copy the Eudora Light software onto your hard disk.
      The latest version of Eudora Light for the Macintosh
      can be found at ftp.eudora.com or www.eudora.com. (If
      you are installing from diskettes, skip to the next step.)
2.   Restart your Macintosh while holding down the shift key.
      This turns off your Macintosh extensions. (You must hold
      down the shift key until you see the message
      "Extensions off.")
3.   If you are installing from diskettes, insert Eudora Light
      diskette 1 of 2 into your Macintosh diskette drive.
4.   Double-click on the Eudora Light Installer icon to start the
      installation program. The Eudora Light splash screen is
      displayed. Click Continue to display the Eudora README window.
      Note:     The contents of the README window can be printed or
      saved to a file for later review.
5.   Once you have reviewed the contents of the README window,
      click Accept. The Eudora Install dialog is displayed, allowing
      you to select which items you want to install. To see a
      description of an item, click on the item (the description is
      displayed just below the selection area).
6.   To install all of the items, be sure the default item
      Eudora Light is selected and click Install.

      To install just the items you want, select them by clicking
      on each one (hold down the command key to select multiple
      items, and be sure that the Eudora Light item is not selected),
      then click Install.

      If you selected the Eudora Light installation item, the Restart
      dialog is displayed, informing you that your Macintosh will
      need to be restarted at the end of the installation. Click Yes.

      The Eudora Version Selection dialog is displayed, allowing you
      to select which version you want to install.

      680x0
      This is the smallest version. It runs on any Macintosh,
      including Power Macs, but on Power Macintoshes it is
      not as fast as the PowerPC or Universal versions.

      PowerPC
      This version runs only on Power Macintoshes. It does not
      run on standard 680x0 machines.

      Universal (or Fat)
      This version requires the most disk space. It runs on any
      Macintosh, and on a Power Macintosh runs as fast as the
      PowerPC version.

7.   Select the version you want. A dialog is displayed asking you
      where you want to install the Eudora Light 3.1.3 Folder.
8.   Select the destination folder and click Install. The install
      program begins installing the items you selected onto the
      appropriate locations on your disk.
9.   If you are installing Eudora from diskettes, insert the
      appropriate installation diskette when you are prompted.
10.  Once the installation is complete, you are prompted to
       restart your Macintosh.
       Click Restart.

This completes the installation of the Eudora Light software. To find out
how to set up Eudora so that you can send and receive e-mail, see the
"Configuration" section in the README installed with the software, and
also see the User Manual section "Opening and Configuring Eudora." For
details about the files in the Eudora Folder (in your System Folder) and
the Eudora Light Application Folder, see their corresponding sections in
the Reference chapter of the User Manual.

===================================
NEW FEATURES AND CHANGES IN 3.1.3
===================================

Auto-configuration 
________________

Auto-configuration support has been added to Eudora 
by using the Internet standard Application Configuration 
Access Protocol (ACAP). ACAP is a client/server protocol
which allows Eudora to retrieve configuration settings
from a central server. These settings include those
that must be set up for you to start sending and
receiving e-mail, such as your POP account name and
SMTP host. 

In order for you to use the auto-configuration settings, your 
system administrator or service provider must set up a central
server with your personal settings. You can then download
those settings whenever you like. Typically, you would do
so only when you first start using Eudora. However, you 
can restore your settings to their original values at any time 
by downloading them down again.

To download your settings, open the Settings dialog under
the Special menu and click on the Auto. Configure icon. Fill
in the ACAP Server Name and the ACAP Server Username fields; 
your system administrator or service provider should have told
you what to enter in these fields. Click the Fetch
Settings Now button and the Auto Configuration password dialog
box appears.  Type in your password in the password field
and press the Configure Automatically button to download your
settings from the ACAP server.

The following ACAP-related information primarily for use by 
system administrators and/or service providers.

If the "If no account configured, try fetching settings from an 
ACAP server" setting (#217) is on ("y"), then when Eudora is first 
launched (actually any time Eudora is launched without a POP 
account having been specified), the Auto-Configure panel of the 
Settings dialog is displayed. In the absence of that switch, the 
Settings dialog's Getting Started panel would appear instead.

The setting for the ACAP Server is #218, and the setting for the 
ACAP Server Username is #219.

The port ID used in communicating with the ACAP server is 
setting  #10109. 

You can obtain detailed information on setting up an ACAP server 
to support Eudora clients on the Eudora web site. go to 
http://www.eudora.com/techsupport, click Frequently Asked 
Questions (FAQ), then click Automatic Initial Configuration with ACAP.

Note: The upcoming version 2.0 release of the Eudora WorldMail Server 
will support auto-configuration of Eudora clients.


Pre-configuring the POP server
__________________________

System administrators can now pre-configure Eudora by putting 
the Mail Host (POP) server name in the Settings dialog, so that 
the user needs only to add his or her account name. When Eudora 
is launched, it displays the Getting Started window of the Settings 
dialog, the Mail Host (e.g., domainname) displaying the correct 
Mail Host setup in your Settings panels.

For example, suppose the Mail Host you required was assigned 
xyz.qualcomm.com. When you start Eudora, Getting  Started automatically 
displays xyz.qualcomm.com in the Mail Host field.  You just need to 
insert your username in the Username text field.


=====================
LICENSE AGREEMENT
=====================

QUALCOMM Incorporated

License Terms for Eudora Light Version 3.1.3 - Macintosh Platform

QUALCOMM grants to the user a nonexclusive license to use this Eudora
Software solely for User's own personal or internal business purposes. The
user may not commercially distribute, sublicense, resell, or otherwise
transfer for any consideration, or reproduce for any such purposes, the
Eudora software or any modification or derivation thereof, either alone or
in conjunction with any other product or program. Further, the user may
not modify the Eudora Software, other than for User's own personal or
internal business use.

THE EUDORA SOFTWARE IS PROVIDED TO THE USER ''AS IS.'' QUALCOMM MAKES NO
WARRANTIES, EITHER EXPRESS OR IMPLIED, WITH RESPECT TO THE MACINTOSH
EUDORA SOFTWARE AND/OR ASSOCIATED MATERIALS PROVIDED TO THE USER,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY OF MERCHANTABILITY, FITNESS FOR
A PARTICULAR PURPOSE OR AGAINST INFRINGEMENT. QUALCOMM DOES NOT WARRANT
THAT THE FUNCTIONS CONTAINED IN THE SOFTWARE WILL MEET YOUR REQUIREMENTS,
OR THAT THE OPERATION OF THE SOFTWARE WILL BE UNINTERRUPTED OR ERROR-FREE,
OR THAT DEFECTS IN THE SOFTWARE WILL BE CORRECTED. FURTHERMORE, QUALCOMM
DOES NOT WARRANT OR MAKE ANY REPRESENTATIONS REGARDING THE USE OR THE
RESULTS OF THE USE OF THE SOFTWARE OR ANY DOCUMENTATION PROVIDED THEREWITH
IN TERMS OF THEIR CORRECTNESS, ACCURACY, RELIABILITY, OR OTHERWISE. NO
ORAL OR WRITTEN INFORMATION OR ADVICE GIVEN BY QUALCOMM OR A QUALCOMM
AUTHORIZED REPRESENTATIVE SHALL CREATE A WARRANTY OR IN ANY WAY INCREASE
THE SCOPE OF THIS WARRANTY.

LIMITATION OF LIABILITY -- QUALCOMM AND ITS LICENSORS ARE NOT LIABLE FOR
ANY CLAIMS OR DAMAGES WHATSOEVER, INCLUDING PROPERTY DAMAGE, PERSONAL
INJURY, INTELLECTUAL PROPERTY INFRINGEMENT, LOSS OF PROFITS, OR
INTERRUPTION OF BUSINESS, OR FOR ANY SPECIAL, CONSEQUENTIAL OR INCIDENTAL
DAMAGES, HOWEVER CAUSED, WHETHER ARISING OUT OF BREACH OF WARRANTY,
CONTRACT, TORT (INCLUDING NEGLIGENCE), STRICT LIABILITY, OR OTHERWISE.

Copyright © 1988-1992 by the University of Illinois Board of Trustees.
Copyright © 1992-1997 by QUALCOMM Incorporated.  Portions of the Eudora
Software were written by Scott Gruby and Pete Resnick. All rights
reserved.

Portions of the Eudora Software were written by John Norstad, Copyright ©
1988-1990 Northwestern University, and David Johnson, Copyright © 1984
Brown University. All rights reserved.

The MacTCP and Communications Toolbox software are copyrighted by Apple
Computer, Inc.  All rights reserved.

AppleTalk, Macintosh and Power Macintosh are registered trademarks of
Apple Computer, Inc.

LocalTalk, MacTCP and Communications Toolbox are trademarks of Apple
Computer, Inc.

Eudora® is a registered trademark and Eudora Pro? and Eudora Light? are
trademarks of QUALCOMM Incorporated.

QUALCOMM is a registered trademark and registered service mark of QUALCOMM
Incorporated.

All other trademarks and service marks are the property of their
respective owners.

October 1997

sendmail freeware site
sendmail commercial site

sendmail 8.12.8 distribution documentation:
../sendmail/FAQ
../sendmail/INSTALL
../sendmail/PGPKEYS
../sendmail/README
../sendmail/RELEASE_NOTES
../sendmail/cf/README
../sendmail/devtools/README
../sendmail/devtools/Site/README
../sendmail/doc/op/op.txt
../sendmail/libmilter/README
../sendmail/sendmail/README
../sendmail/sendmail/SECURITY
../sendmail/sendmail/TUNING
../sendmail/smrsh/README

Pegasus Mail web site
Pegasus Mail for MS-DOS v3.5 for DOS and Windows

Pegasus Mail web site
Pegasus Mail v3.12b for Windows, 16-bit for all Windows versions

1. A spammer may have used your email address for his spam, and you got
the bounce. Mail servers are getting smarter about insisting that email
come from real domains. This helps eliminate the getsome@sexypictures.now
type of return address that's never intended to be used except to satisfy
the requirement that mail has to come from someone. In the past, mail
servers just checked for a return address, so spammers could (and did) put
whatever they wanted there. Now that servers are checking for valid return
addresses, spammers aren't using their own -- they're using yours. This
lets them send all the spam they want while you get the complaints and
bounces.

Friendly little buggers, aren't they?

There is absolutly nothing you can do about this. Until all servers start
requiring authentication (and even then, unless other servers only accept
mail that's been authenticated) the problem will continue.

Fortunately, this minor form of identify theft doesn't damage your
reputation. The headers clearly indicate that the email didn't originate
with you. Some individuals may read the headers and think the mail came
from you (or just reply with a nasty note without bothering to look at the
headers), but organizations like SpamCop and all mail administrators won't
be fooled.

2.  Someone to whom you've sent mail in the past, or who has your email
address in her address book for any other reason, may have a
virus/worm/trojan (like Klez) that sends out mail with forged headers
drawn randomly from the address book.

3. Some spammers send fake bounce messages to trick you into opening the
email.

4. Some virus/worm/trojans send fake bounce messages, too. You click on
the attachment to see what message bounced, and viola! you are now
infected.

5. You may have a worm that's sending mail from your computer without your
knowledge or consent. You typically pick up these programs by running an
executable attachment, or by browsing to an unsafe site with all the
active-content doodads enabled. You should

5a. Turn off all scripting support (VBScript, JavaScript, JScript, Java,
etc.) 
5b. Get a virus checker like F-Prot or Norton Anti-Virus or McAfee.
5c. Update your virus checker definitions regularly
5d. Get and run Ad-Aware 

6. Make sure you don't have SMTP-After-POP3 enabled for your mailbox
unless you absolutely need it.

SMTP-After-POP3 is a workaround for older email clients that don't support
SMTP authentication. When SMTP-After-POP3 is enabled, the mail server will
grant your email address "presumptive authentication" if you've just
checked your POP3 box. This lets the older clients send mail while keeping
your account mostly secure.

"Mostly" is the keyword. Some email servers out there are run by spammers
directly (as opposed to just being hijacked). These nasty servers wait for
incoming email and, upon receipt, immediately try to spam the sender. So
when you fire off an angry letter to someone who spammed you, or reply to
a GreatMortgateRates@4u.com address, you can end up getting spammed within
seconds. 

Worse, the spammer may send email to others under your name. This is the
real danger, because if your account is hijacked this way, the spam really
does come from you, even though it was injected without your consent.

You should only enable SMTP-After-POP3 if you absolutely need it.