What does an “Undeliverable” email message mean?

This post is not so much a tip as an explanation of what exactly those Undeliverable messages we all get from time to time mean. More importantly how to decipher them and understand where the email we sent went wrong.   As a form of communication email has now been around for some time and is now accepted as a standard form of communication.  It’s quick and very reliable.  I’m not saying emails don’ t go astray but probably no more often than standard postal mail.  The main advantage being the person you send it to can receive it within a few minutes.

But, what if they don’t receive it?  What if you get one of those “undeliverable” messages. They act like the return address on the back of a letter, and mean the email could not be given to the recipient.  They are actually rather easy to decipher, you just need to look at the email from the computers point of view.

An email address is split into two parts, the bit before the @ and the bit after it.

The bit before the @ is the persons email name and the bit after is where they and lots of other peoples emails “live”.  So with the email address joe.bloggs@hotmail.com Joe Blogs is the guy you are emailing and his (plus millions of others) emails “live” on Microsoft’s email server hotmail.com.

Now an email can be undeliverable for two reasons,

1. The server does not exist or
2. The server exists but the person is not on that server.

Issue 1 is usually caused by a typo in the server side of the email address (the bit after the @) These errors usually appear very quickly after you send the email. So joe.bloggs@hotmail.com exists but joe.bloggs@gotmail.com does not.  So if your undeliverable email says it is from “system administrator” that usually means your PC cannot find the server.  There is one other reason why you could get this message and that is because your internet connection is down.  Rather than say that the internet is down your PC may give this or other messages coz it’s stupid like that and anyway saying the Internet is down would be too easy.

Issue 2 is usually from administrator or postmaster@ the server you sent the email too. So in our example it would be postmaster@hotmail.com.  In this case the typo is going to be in the first part of the email address. So joe.bloggs@hotmail.com exists but joebloggs@hotmail.com (without the dot) does not.  The other reason the person may no longer exist on that server is because they no longer use that email address or they have been removed. The usual reason people lose their email address is because they changed internet suppliers. So joe.bloggs@btinternet.com becomes joe.bloggs@virgin.net.