Q: The following message appears every single time I try to send/receive email. Mucho annoying! I am not a computer geek in any way, shape or form, but I did try to research this problem online. Unfortunately, if the explanation is in geek it might as well be greek to me. I use Windows Live Mail, if that is important. By the way, I do read your column weekly, but understand very little of it. I keep trying though. Thanks!
The message could not be sent because the server rejected the sender's email address. The sender's email address was '[REDACTED]'.
Subject 'Read: Your Quest Diagnostics Invoice for Lab Services is enclosed'
Server Error: 550
Server Response: 550 5.1.0 Authentication required.
Windows Live Mail Error ID: 0x800CCC78
– Kimber J., Niceville
A: I appreciate that you consider yourself an entirely non-technical, non-geeky user, Kimber. But there’s almost no way to talk about problems with an email account without using a certain amount of technical jargon. Before I proceed, I’ll try to dispense with some of the explanation. Pardon me if this is over your head, or if it’s so simplified that I insult your intelligence. No offense is intended either way.
When considering email, one may draw a direct analogy to physical snail mail. Emails are like letters that get sent back and forth. Your email client, in your case Windows Live Mail, is akin to your mailbox. You put letters into it to send, and when new mail arrives, that’s where it goes. With snail mail, behind the scenes there is the post office, which consists of a series of mail-handling facilities. A physical letter travels from your mailbox to your local post office, then is sent via various means to the recipient’s post office, where it ultimately winds up in his or her mailbox. The same thing happens with email, except the post offices are computers running a special kind of software called an email server. This dedicated software fills all the roles of postal employees in a physical postal facility, from the clerk at the counter, to the letter carrier that picks up and delivers your mail. In order for all this to work in email, all of the computers must be connected to the internet, and all must speak compatible languages so that they can understand each other as the emails are being exchanged. This is called a protocol, or more specifically, a mail-transfer protocol. A protocol consists of a set of rules that both sides of the connection must adhere to in order for the email to go. Modern email uses a well-established set of protocols, developed and standardized a long time ago.
In addition to simply exchanging the email, it must be kept safe from tampering and snooping along the way. After all, it wouldn’t do to give all the online bad guys free reign to inspect every email that you send or receive, would it? This security is implemented in multiple places. First and foremost, you must provide your email account’s password for every transaction you do with your mail server. It’s just like logging into your computer – if the username or password are wrong, you can’t proceed. Second, a type of encrypted connection called Secure Sockets Layer or SSL, is often used, so that if anyone happens to intercept the transmission, they will only see gibberish, since the connection is basically scrambled.
Now that you know how email works (and I’ve used up most of my column space for the week explaining it to you) let’s address your actual question. The answer that you seek, Kimber, is hidden in plain sight – right there in the error text that you provided, although it doesn’t pinpoint what you can do to fix it. The most important phrases are where it says “the server rejected the sender’s email address” and “Authentication required.” The mail server (your electronic post office) is refusing to accept email from the address you provided, because it was not able to authenticate that address. In this context, “authenticate” means that Windows Live Mail must prove to the mail server that you are who you claim to be. I noticed that the email address in the error message is the same one you used in your personal information. So I don’t think that’s the problem. I suggest you double-check your password though. That error could mean the password you supplied doesn’t match the password that Cox has on file for you. Your other settings look correct to me. The values for Server, Protocol, Port, and SSL all appear to be as they should. The only other possibility is that Cox has blacklisted your email address. I’ve seen this happen before, when a spammer uses someone’s account without their knowledge. To Cox, it looks like you are sending SPAM, and to defend against it, they simply deny that account the ability to send mail. Regardless, a call to Cox Customer Service is in order. Ask them to make sure your account isn’t blacklisted, and for help resetting your password.
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