First you need to know if you are on a Blacklist. Usually your suspicions will be aroused when a mail "bounces back" undelivered. Read the error message carefully and if it contains words like REJECTED or SPAM then you know your email was rejected for containing spam or you are on a blacklist.

By checking the EMAIL HEADER you should be able to determine which spam rules have been broken. See SPAMMY CONTENT rules to find out what you CAN and CANT send in an email. You may be surprised for example, that you shouldnt use ALL BLOCK CAPITAL LETTERS IN THE SUBJECT LINE. If your email simply contains spammy content; fix it and re-send the email.

To find out how to view Email Headers click this Calco Guide: Viewing Email Headers (aka internet headers)

However if your email appears NOT to be spam then you should inverstigate whether you are on a spam list.


Method of finding if you are on a Spam Blacklist

First of all you need to know that spam databases use IP addresses (more likely a block of IP addresses*).
*This can be grossly unfair as it means that 1 person on your server (assuming you use shared mail servers) is misbehaving and you will be blacklisted because you are in the same range of IP Addresses.

To "convert" your email address to an IP address you need to start with an MX Lookup. We suggest using MX Toolbox for this as there are serveral other good tools on this website.

Look Up Your Mail Server's IP Address (this will open a new window - this page will be underneath)

You can then click the link that says Blacklist Check (over 100 different data house checks)

With a bit of luck you should see row after row of green ticks. If you DONT and see red crosses; it means you or someone on the same IP address has been spammy.

It may well be the case that the spam listing goes away all by itself in 3 to 5 days. This is normal practice if you are considered a minor spammer. Only repeat offenders do not receive this benificent treatment. Sadly one or more of the Spam database providers ask for money to "expidite" your removal from their lists.

Assuming you have a problem that doesnt go away in a week; you should go to the websites of the Spam Databases that list you as a spammer and find the page that is titled something like :- I believe I am unfairly listed as a spammer ... or ... I wish to be de-listed from your spam database etc.

Typically you fill in a form and request de-listing. A few days later they will confirm or deny your de-listing with a stern warning that if you re-offend, there will be dire consequences!


Conclusion and Advice

Build your own Mailing List or have a professional do it for you. Its not that difficult if you are a reputable company with bona fide products or services. Most customers respond well to special offers if they "sign up".

If you are sending cold emails to potential prospects then do it via a reputable agency or at the very least a temporary email address from a huge company like Google (GMail) or Microsoft (Hotmail). However the latter two companies wont allow you to send spam to tens of thousands of businesses.



What is Spam | Glossary of spam terms | Sending people emails with ALL CAPS in the Subject |

| How to view my email header |


How to view my email header




Its actually unusual for email to be LOST. Its far more likely there is a programmatic reason for the mail being diverted from its true destination.


A) You have no permission from the ISP to use your own email address. (BT do this)

B) The destination mailbox is FULL. You will see a message when the mail fails to deliver to the effect the recipient has exceeded their QUOTA or words to this effect.

C) The destination email address doesnt exist. Again you will recieve a message back from the mail service that the email address could not be found.

D) The message was too large to be delivered. Sadly this is not well defined in error messages, but if the mailserver does generate a message it will be something like "Message eceeds maximum message size (5000000)" This is telling you the maximum attachment is 5mb. Most ISPs have an attachment limit - it varies from 2mb - 50mb. Realistically you should be using another method to send files over 5mb anyway as you risk filling up someone's mailbox, especially now that modern cameras generate images of 5mb per picture. Try Microsoft's Sky Drive or Dropbox

E) Your email contains a virus (or an .exe or .com file) Simply clean your computer or re-name your exe and com files to something benign like .txt

F) The email was REJECTED by the recipients Mailserver. This is the SPAM ERROR message. There are TWO options:- Either the actual message you sent contains SPAMMY CONTENT or you are on a SPAM BLACKLIST!

If you are on a blacklist see the main contant of this page on how to deal with this tricky problem.



It is an offence in the UK (and in most countries) to send unsolicited email to a list of businesses, obtained legally or otherwise. This means if you buy a list of all the business email addresses in the UK "from a guy on the internet" and send email to them you are guilty of an offence punishable by a fine of 5000 pounds (or unlimited fine if the case goes to trial by jury)

Not only that... the email address that you send these emails from will probably be BLACKLISTED.

You should also know that MOST internet providers do not allow you to send unsolicited bulk email (spam) to large lists; even if you have a dedicated or virtual server.

To "get around" this problem you have to build a list of email addresses, every one of which must confirm that they want to be part of the list. This is called Double Opt In

If you send to someone else's list - ie employ an agency to bulk email; chances are that the recipients will delete your email without reading it. Again that is why it it much better to BUILD your own list.

We suggest you use AWeber or Mailchimp. They provide lots of good tips for professional mailshots


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