Why messages are treated as SPAM

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This article outlines some of the reasons why an email message gets flagged as spam on a recipient's end.

The amount of the information that we receive these days is overwhelming. It’s already hard to filter the messages that reach our inbox – urgent ones from those that can wait, personal from public, important from those less important.

If you add to that a couple dozen SPAM emails, the task becomes extremely difficult. No wonder that internet service providers and other companies are taking drastic measures to stop unwanted junk-mail.

Of course, there is a cost of those measures – many of anti-spam blockers are stopping even legitimate emails.  If you have a problem sending a message to the recipient – that might be the case.

The reasons why this is happening might be:

-    SPAM blocking software “thinks” that your message is a spam because of its content

-    Email is sent from the address considered by SPAM blocker as the spammer.

When your message is processed by the content scanner it receives points for every possible SPAM-like behavior. If it collects too many points – blocking system is marking your e-mail as spam.

There is a number of the reasons why your message is treated as spam:

-    Sexually explicit terms, or phrases such as "adults only", "over 18" and the like.

-    Certain drugs - again typically linked to sexual performance or characteristics.

-    SHOUTING. Spam filters will often consider shouting (or alternately SHOUTING) as sales copy.

-    Fake, inconsistent or illegal return addresses. Or a "reply-to" address that does not match the "from" address.

-    HTML Email. Spam filters consider HTML email as having a higher risk of being spam than plain text email.

-    Marketing terms. Because so much spam is, in fact, direct sales marketing, many filters now look for various words and phrases such as "satisfaction guaranteed", "free offer", or any of sales kind wording and give that a higher probability of being spam.

Of course, if you have to use any of those expressions, words or content, it is not “wrong” by definition. You just have to be prepared that more you have it in the message the bigger chance is that you might be stopped at the doorstep.

The other case, IP address considered as a spammer, is no less common. If for some reason, your IP number is being related to spammers, your message might not pass the filter. It’s even harder to identify the problem if you are not receiving the usual, bounced back message, saying “undeliverable”. If this is the case – test if your IP is blocked. Send the message using other internet service provider, e.g. from your friend’s home computer. If his message gets trough – better check your IP, if it’s not blacklisted. One of the sites that provide SPAM database lookup for blacklisted IP numbers is whatismyip.com.

The last resort, when you can’t identify the cause of undelivered messages, or when your IP is blacklisted, is to contact your ISP. They are managing and “owning” IP numbers and are responsible for keeping spammers at bay, as well as keeping it “clean” for you.


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Expert Comment

by:Andrew Leniart
Blocking spam has always interested me and there are some excellent revelations in this post.  Thanks for writing it!

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