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2. Email.

2.1 I just sent an email to my friend, but I got a message back saying it couldn't be delivered! What's up with that?

Well, this depends a lot on where you were sending the email.

If you sent an email to a friend who is not a Coinet user, then it's not our mail server that said the user didn't exist. Your friend's ISP has its own mail server, and it is the final authority on users that exist there. Our mail server connects to other mail servers on the Internet, and it says it has email for a specific user there, and if the other mail server says there is no such user, then there is no such user!

2.2 How do I read your mail server's failure notices?

Failure notices sent by our mail server are very easy to read, once you have a basic understanding of the format. Below we step through a typical failure notice, then we will show you other error messages the mail server may specify.

Hi. This is the mail transport agent at
I'm afraid I wasn't able to deliver your message to the following addresses.
This is a permanent error; I've given up. Sorry it didn't work out.

Above we see an introductory paragraph, in human language, that tells you one very important fact: This is a permanent error; I've given up. Sorry it didn't work out. That means the mail server will not ever try to deliver this and only this particular email again. It does not mean that the mail server will not ever again deliver another mail from you. The message sounds like it was written by a human (and it was, when the software was coded), but remember this is completely automated, there is no human that processes each and every email.

<>: does not like recipient.
Remote host said: 550 <>... User unknown
Giving up on

Immediately below the introductory paragraph the mail server will list each recipient of this email that had a delivery failure. It could be that you sent this email to five people, but only one email address is listed in the failure notice--you can safely assume the other four recipients did in fact receive your email.

Let's look closer at the above. The first line shows the email address that failed; it's important to pay close attention to this address, since most bounces are caused by misspellings. And take note, just because the address is in your mailer's address book does not mean it's entered in there correctly. In addition, that address is exactly what your mail software said the recipient should be. You may not think that's what you had in there, but the mail server doesn't lie; it just does what it's told.

The next line, does not like recipient. is telling us that the remote mail server (the mail server that handles email for your recipient) rejected the mail after ours said to whom you wanted the email delivered. The IP address,, is mostly for diagnostic use by mail admins, since an Internet domain may have more than one mail server, it helps figure out if a particular mail server is misbehaving or not.

The next line is the most important one here. If our mail server has at least successfully talked to a remote one, then it will insert whatever response it got. The part Remote host said means just that--this is what the remote server told ours after it specified the recipient, which we determined from the line above this. Specifically, it said 550 <>... User unknown. In ``mail server speak'' the code 550 means that the error is permanent (and this is why our mail server told you ``This is a permanent error,'' it's just following the advice given by the remote server), then it says something in human-readable output for our benefit, <>... User unknown. So, we know that our mail server connected, said it had an email for and after specifying this, the remote server said User unknown. That address is not a valid local address, in other words.

We move on to the copy of the mail provided by our mail server:

--- Below this line is a copy of the message.

Return-Path: <>
Received: (qmail 27858 invoked by uid 1947); 18 Nov 1997 22:51:16 -0000
Message-ID: <>
Date: Tue, 18 Nov 1997 14:51:16 -0800
From: "Me" <>
Subject: hi friend!
Mime-Version: 1.0
Content-Type: text/plain; charset=us-ascii
X-Mailer: Mutt 0.85

hey.. how's it going?


Our mail server has helpfully inserted the complete email you sent, including any attachments, so that you can figure out better exactly which mail you sent bounced.

In any case, look carefully at the bounce you got. Chances are, you'll notice that you misspelled your friend's email address, or misspelled the domain name.

It's important to note that our mail server does not return emails without a very good reason.

Some other error messages, and what they mean.

There are a myriad of reasons why an email can bounce. Unfortunately, with the way email works and has worked for around thirty years, you can never know for a 100% certainty that your email was delivered. With failure notices, we know for more than 99.9% of mail sent, but there is still some occasions when an email will disappear and you won't get a bounce, likely due to misconfiguration at some remote mail server.

Below we list some other error messages the mail server may put in failure notices.

Sorry, I couldn't find any host named (#5.1.2)

The mail server checked the DNS for some place to send email for ``,'' and there is no such data in the DNS. It usually means one of two things, either the domain name just plain does not exist on the Internet, or you've misspelled--again, double-check spelling.

Sorry, I wasn't able to establish an SMTP connection. (#4.4.1)
I'm not going to try again; this message has been in the queue too long.

The mail server did find out from the DNS where to send mail for, however it could not connect to that domain's mail server(s). The part this message has been in the queue too long, means that the mail server tried for seven days, periodically, to connect to their mail server(s), and it failed each time. After a week in the queue, the mail server will give up and bounce it back to you. You will probably have been receiving deferral notices from our mail server during that week. See below.

Sorry, I couldn't find any host by that name. (#4.1.2)
I'm not going to try again; this message has been in the queue too long.

Similiar to the first example, but in this instance the domain,, does exist, however the mail server can't find out where to deliver email for them. The DNS specifies to where email for a domain is supposed to go, so either that domain's name servers are unreachable or not answering, or their admin has failed to enter such data into their name servers. That could be by mistake, or intentional.

2.3 I'm telling you, it's not possible that this email bounced, because I am just replying to an email that was sent to me. They can't send me an email without a valid address.

Please be aware that even if you receive an email from someone that doesn't mean their return address is valid or even works.

What this means is that you may, from time-to-time, receive email from persons who have mistyped or otherwise incorrectly specified their return address in their mail software settings. When you reply to their message, your mail will bounce.

What can you do? Well, if their error is obvious, just fix their email address in the To line of your mail composition, and make sure to let them know their error!

The other possibility is that your friend's ISP's mail server is misconfigured. If you contact your friend and tell them of the bounce and they assure you that address is correct, it could be that mail server has problems. In that case, you should be a good netizen and contact their postmaster. It is required that all domains have a working postmaster address, and to reach them you simply email postmaster@domain.tld. For example, to reach Coinet's postmaster, send an email to When telling the postmaster of the trouble, make sure to forward the failure notice you received along with your note.

2.4 I was sent some junk email. Within it said to reply or send email to them to get removed, but my mail to the junk mailer is bouncing!

Congratulations, you are now among millions of Internet users that have been spammed. ``Spam'' is a term used on the 'net to describe junk email. The nice people who decide to fill our mailboxes with junk are known as ``spammers.''

Spammers almost always lie; spammers do not really want you to reply to them to get yourselves removed from their email list. If they do provide a valid address to mail them, you writing to them just confirms that your address works and someone reads it. For these reasons, it's best to not reply to spam.

So I should not reply to spam. What then should I do with it, just delete it?

You can just delete the spam if you so wish. Even better, however, is that you can complain to the spammer's Internet Service Provider. Most legitimate ISPs will cancel a spammer's account if they receive confirmed reports of their transgression.

Finding out exactly where a spam came from is not for the faint of heart. Spammers forge mail headers and their return address to help disguise themselves. There is a web site that you can submit the spam to and it will decipher the headers for you and mail complaints. The site is called SpamCop and you can reach it at

Alternatively, you can forward the spam you received to and we will complain for you. Make sure to forward your spam with its complete headers, otherwise we can't determine exactly where it came from. You will likely need to be viewing the message with full headers in order to get it forwarded with them. Please see your mail software's help files or call us to learn how to do that.

2.5 My friends tell me that they keep sending email to me and it's bouncing!

We've found that the vast majority of problems like this are because users send out email with invalid return addresses (the From line in an email, usually). When your friend replies to you, their email software will use the return address listed in your email to them. Well, if your return address is wrong and your friend doesn't notice it, it will certainly bounce.

If you are certain that everything is OK with your setup, please give us a call. It would be very helpful if you had a copy of the bounces that your friend(s) are getting, or you can tell them to email the bounces to

Netscape users:

Most problems with return addresses come from people using Netscape to send and receive email.

It's very important that you make sure you have specified a correct return address in Netscape's mail options. Specifically, problems with Netscape mail tend to be caused by users using an address like this in the section labeled ``Email address'' in Netscape's mail options:

Your name

A correct options setup would be:

Name field:                  Joe Public
Email address field:
Reply-to address field:

2.6 I am getting email but there is nothing in the message!

Netscape users often have trouble because the mail window in Netscape uses panes. Sometimes the horizontal pane has been dragged all the way to the bottom and all that you can see is your inbox. To fix this, drag the pane up the window until you can actually see the text of the email you are viewing.

2.7 I'm having big trouble retrieving my email. I keep getting the same messages over and over, or the transfer of my first message is timing out.

Very often this is due to you having been sent a very large email (1 megabyte or larger). Dialup users can sometimes have trouble when trying to download large emails. If you think this might be your problem, please go to the IMAP webmail gateway (IMP) at From there you can view and delete email in your mailbox using your web browser. Once deleted by IMP, then it won't trouble your regular mail software. At the login screen, make sure to read the link named New User Introduction if it is your first time using IMP.

If all else fails, then call us and we can remove the offending message for you.

2.8 My mail software says I have more emails than it's downloading from the server.

There are two things you should probably check.

Check if mail software is configured to ignore large emails.

Your mail software is likely configured to ignore messages larger than a certain size. We've seen this with Netscape and Eudora Pro, especially. When configured like so, it will leave those large emails on the server, which will make your mailbox grow if friends keep sending you large attachments.

If you are using Netscape (especially from our CD that installs version 4.04), click on the ``Edit'' menu, click on ``Preferences,'' double-click on ``Advanced'' then click on the ``Disk Space'' subcategory. Uncheck the box similiar to ``Don't download messages larger than ...''

If you are using Eudora Pro, click on ``Tools'' then ``Options'' then on the ``Incoming Mail'' icon. Uncheck the box that says ``Skip messages larger than ...''

Check if your mail software is leaving read messages on the server.

If you are using Netscape earlier than 4.5 (our CD installs 4.04, so yes if you used our CD), click on the ``Edit'' menu, click on ``Preferences,'' double-click on ``Mail & Groups,'' click on ``More Options'' then make sure ``Leave messages on server'' is unchecked.

For Netscape 4.5 or later, click on the ``Edit'' menu, click on ``Preferences,'' double-click on ``Mail & Newsgroups,'' highlight ``'' up top and click the ``Edit'' button. Next click the ``POP'' tab then make sure ``Leave messages on server'' is unchecked.

If you are using a mailer other than Netscape, please check its help files (Click on ``Help'' then choose ``Contents'') or call us.

2.9 I got an email from the system administrator saying I have too much mail!

Please see the above question and answer.

2.10 When my mail software connects to Coinet, I get the message ``Authentication failed.''

Many new users make the mistake of specifying that their POP3 username is That's incorrect! Our POP server will reject your connection because of an invalid username.

Of course, if you are sending the wrong password, that will also cause you trouble. Remember to check your caps lock key.

Exception to above: Eudora users, however, will specify in their settings that their POP account is

Your username is the portion before the ``@'' in your full email address.

2.11 I should be able to get huge emails, all of my friends do. I think your mail server is broken.

There are a number of issues that make the sending of extremely large files via email a bad idea. There are much better ways to get large files. For example, most large files can be had if the sender decides to not attach it, but rather send an email with a URL so that you can go on the web and download the file yourself if you wish. There is also FTP. Both of these protocols were designed for the transfer of large files--email was designed for the transfer of small to moderately-sized messages.

Some mail software will stop the downloading of large messages if it takes longer than the specified auto-mail-check time. What that means is some users set their mail program to check mail automatically every few minutes. Well, if it's set for auto-check every 10 minutes and it will take 15 minutes to get the large email, then the mail software may reset itself and the download will fail. Check your mail settings and disable or increase the auto-check time interval and see if that helps.

Files sent via email are typically increased in size by around 70%! That's because email can contain only text, and most files sent via email are binary. Hence, they must be encoded as text, which causes the bloating of file size.

2.12 I want to send out a mail with a large attachment to a bunch of people. I know sending via email is not very efficient, what's a good way?

All Coinet customers have personal web space available. So, you can upload a file to your web space, then you can email your friends the address to go and get it!

You will need to follow the directions at to get the file uploaded. Let's say you uploaded a file named ``elfbowl.exe.'' If your account name at Coinet is ``joeuser'' then tell your friends to access the file using the URL

The initial work of getting to know how to do this is worth the trouble in the end. Make sure to delete old files from your web directory every so often so you don't outgrow your disk quota.

This also ensures that only those that really want to get the file will retrieve it. If you send it via email, they haven't any choice but to spend time (sometimes a lot) downloading it. Maybe they don't want a new screensaver.

2.13 I got an email that told me to forward it to everyone I know. Should I?

No. Don't do it, ever. Really. It's probably a hoax mail, especially if it talks about making a lot of money or mentions a really bad virus.

2.14 I sent an email and a few hours later received something from MAILER-DAEMON. It says my email has been undeliverable for 4 hours. Is your mail server working?

Yes, our mail server is doing exactly what it's supposed to!

It happens quite often that email you send may not be delivered right away. This can be due to a number of reasons, such as:

The remote mail is server down.

This is the mail server that handles the email for the recipient's domain. Computers are machines, remember, and they can fail.

The remote mail server is refusing connections.

This is likely because the remote machine is overloaded with connections, as often happens when sending email to large companies such as AOL.

The remote mail server is unreachable.

This can happen when there are problems with a router between us and the remote mail server.

You are using an invalid return address.

Many mail servers on the Internet are now checking that the return address of incoming email points to a valid domain name. If you have an error in your mail setup, such as misspelling ``'' or adding a space AFTER, your email will not be delivered. Instead, the remote mail server will continue to reject it with a ``soft error'', meaning that it isn't rejected outright, just deferred.

So, if you are actually being told by our mail server that your email has been delayed, you may assume that things are perfectly well on our end! Our mail server will keep trying to deliver your email on a regular basis for seven days. If, at the end of that time, it is still not deliverable, you will be sent a failure notice and your email will be removed from the queue.

If you want to know specifically why your message is being deferred, forward the deferral notice to and we'll check it out.

You mention that using an invalid return address can cause my email to not be delivered. How can I make sure it's set correctly?

You can send yourself a test email. After you have downloaded the email you sent to yourself, look closely at the return address. Pay particular attention to any spaces that shouldn't be there. If it looks like < >, then you'll need to fix it.

2.15 Who is this MAILER-DAEMON guy?

MAILER-DAEMON is not actually a real person. It's the address that the mail server uses when it needs to send email for whatever reason.

If you receive an email from MAILER-DAEMON, it will always be some sort of notification regarding email that you have sent. Sometimes, it will be the MAILER-DAEMON here at Coinet, and other times it will be from a remote mail server, probably someplace you have recently sent email.

To define the word, a ``daemon'' is a program that runs all the time. Naturally, our mail server is running 24 hours a day, so therefore is considered a daemon.

2.16 I'm getting a lot of junk email. How can I filter this?

Check the Coinet User's Services web pages at, where there are mail filtering options you can choose from.

2.17 Do you sell your client list?

No. Coinet never sells nor distributes our clients' names or email addresses.

2.18 I use Netscape mail from your CD, and it prompts me for my password all the time. It's a pain.

Yes, the version of Netscape on our CD will prompt for your password the first time you check your mail in a particular session.

You can work around this by clicking on ``Edit'' then choosing ``Preferences.'' Double-click on ``Mail & Groups'' then click on ``Mail Server'' on the left-hand side. You'll see a button that says ``More Options.'' In there, click on ``Remember my mail password.''

2.19 I'm using Microsoft Outlook Express and am having a devil of a time with my mail.

Outlook Express is generally a tech support nightmare for ISPs. If you are having chronic problems with it, we recommend switching.

You can obtain Netscape by getting the install disc from us, which is Coinet's web browser of choice. It comes with easy-to-use mail software.

If you don't want to use Netscape, our other recommendation is Eudora at

2.20 I'm using Outlook Express, I just installed anti-virus software and now can't get my mail!

It seems that later versions of some anti-virus software reconfigure Outlook Express in such a way that it stops working. The virus software changes the incoming mail server setup to point to That IP address means ``localhost''--in other words it will connect to your own computer to try and get your mail, instead of our mail server. The reason it does this is that your anti-virus software is supposed to proxy your POP3 connection to our mail server, and check for viruses while it is downloading your mail.

We don't know why the anti-virus software fails to properly proxy your POP3 connection. It seems that even if the software is setup to NOT proxy, it will still reconfigure Outlook Express. Hence, the connection to will fail. You should call the company that programmed the software for assistance.

If you see an error message from Outlook Express similiar to this, then you have this problem. Pay particular note to Server: '', that's how you know it's connecting to localhost instead of our mail server (it should say Server: '').

The connection to the server has failed. Account: '',
Server: '', Protocol: POP3, Port: 110, Secure(SSL): No, Socket
Error: 10061, Error Number: 0x800CCC0Eil.  

See and follow the steps to ensure Outlook Express is configured properly.

2.21 How do I setup multiple email accounts for my family?

We have instructions on how to do this for Outlook and Netscape online. See

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