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There's no doubt that email is a fundamental tool for business, but taking it for granted will cost you dearly. It’s based on Jurassic technology which simply hasn't kept up with the times. Undeliverable mail for no understandable reason, unknown recipient, or worse still - no indication that your message hasn't even been delivered!
Despite popular belief a single and direct 'source-to-destination' connection is never actually established during email communication. The message is passed from one server to another and another until it finally reaches its intended recipients mailbox. This 'connection-less' method of communication is generally acknowledged as unreliable since it has no built-in mechanism to guarantee successful delivery. Read the small print from your ISP's T&C and you'll see the all-time favourite 'Best Effort' phrase being used lavishly whatever the tariff you're on. External methods for confirming delivery success are also considered unreliable. The all-time favourite 'Request Delivery Receipt' option tends to be thought of as a panacea to these issues. Spammers use these features as vectors for attacks and are largely being ignored by servers and service providers in an attempt to reduce the incidence of spam to their client-base.
At the highest level of abstraction an email message leaves the senders PC and is delivered to the recipients PC apparently instantaneously. Simple and seemingly unfailing. At the lowest level, it’s unbelievable it works at all, so we'll stay well clear of those depths.
 An email message journeys through your local area network (LAN) and then the internet in a best-effort attempt to reach its final destination. When you compose a message, address it, and finally hit the Send button, the message races for the Outgoing email server. In tech lingo - the SMTP Server. This servers' role is to extract the recipients' address and establish contact with the recipients' SMTP server. Once connectivity between the two servers is established the message will get transferred across and stored in a mailbox at the recipients' Server – the POP or IMAP Server. It will sit there until the recipient 'pulls-down' the message from the mailbox by hitting the send/receive button or automatically if the email client is configured to do so.
Lets add one further level of complexity to this scenario – Anti-this and Anti-that Filtering. Once the message sets off from the senders’ pc, it gets scanned for viruses and spam content and then allowed to proceed to the server. On the recipients side the message is scanned for the same content again and finally allowed through to the receivers’ mailbox. When the recipient actually 'pulls-down' the message, it is scanned once again for viral and spam content before finally being stored and displayed on the recipients’ pc.
Troubleshooting the basics.
The recipients' address - I know I know I know, but it’s the single most likely cause of mail delivery problems so deserves a mention. Most servers do actually send you an email back stating that the message could not be delivered because no such user was found, but these are in rapid decline due to anti-spam measures.
Internet Connectivity - Without access to the internet, the message has no medium on which to transfer across servers. So do check that you can surf the internet to rule out this possibility.
Email Client Configuration – Sometimes the SMTP server which the email client points to is not always accessible. Try pointing to your ISP's SMTP server since this will provide you with the most responsive experience. If you don't receive any error messages when hitting send/receive then you can safely assume the server settings in your email client are set-up correctly. In most email clients go to Tools > Options > Accounts and have a look at the Servers area. If you're unsure of the server names, contact your Internet Service Provider support desk or your System Administrator.
The Firewall doing its thing – Sometimes firewall updates close-up the essential ports used for email communication. This may especially be the case if the default windows firewall is disabled in place of a third-party product such as those bundled with anti-virus that provides some form of internet security. Do make sure that Port numbers 25 (SMTP) and 110 (POP) or 143 (IMAP) are actually open.
Blacklisting – If you and your colleagues are unable to send email to anyone outside of the office, your ability to send email may be deliberately blocked by your ISP. This typically happens when your network has fallen victim to spammers. Their method typically involves the installation of a small program on a pc within your network without the users consent or knowledge. This application, referred to as a 'bot' forms part of an international network of literally thousands of bots, forming what is known as a bot net. Under the control of their anonymous owner, the bot net will receive commands to send huge amounts of unsolicited email from your network without your knowledge. An early indicator of this activity may be slow internet access. Eventually Anti Spam watchdogs will track down the origins of these emails and suppress your ability to send email by blacklisting your IP address (the number which uniquely identifies your network on the internet). Shortly afterwards, your ISP will block all SMTP traffic from your IP address. To check if you're blacklisted you need to first identify your public IP address and then bounce this address off a watchdog's site. To find your public IP address, visit www.whatismyip.com. To check your blacklisting status type your public IP address into www.anti-abuse.org and view the results.
Happy emailing!
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Where's that eMail?
