Thursday, 19 April 2012

Are your Legitimate Emails being Trashed?

If you are sending out a newsletter, you probably know that, even if it is perfectly legitimate, spam filters may block it by mistake. The "false positives" issue is a huge problem for legitimate senders: anti-spam filters have no way of knowing whether a message is spam or not; they can only check whether it looks like spam. They give each incoming message a "spam score", and if the score is high enough the message is redirected to the recipient's junk folder or even not delivered at all. Only messages with a low spam score make it to the recipient's mailbox.

IMPORTANT TIP: Even the most well-written message will do you no good if it never arrives in your recipient's e-mail inbox. Make sure your welcome letters and other messages don't fall prey to the various spam filters used by all e-mail hosts. These filters typically identify words (especially if used repeatedly in an e-mail) they deem likely used in spam. Fortunately, there are numerous free online tools you can use to help ensure your messages don't get flagged as spam and instead reach your recipient's inbox as intended. For maximum effectiveness, I recommend you check each of your messages using two or more of these checkers:

MailingCheck incorporates SpamAssassin engine, which is the most popular antispam filter used by ISPs around the world, and analyzes your e-mail message in order to calculate its "spam score" based on its content: the higher the spam score is, the higher is the chance that, once the mail has been sent, it will be filtered out as spam. This will allow you to correct any major problem before you actually send out your mailing.
MailingCheck can be used by legitimate senders only, in order to track down any problem with their legitimate (opt-in) messages' delivery and comply with SpamAssassin guidelines for senders; any abuse - including using the tool for any task related to sending unsolicited messages - is prohibited.

The integrated SpamAssassin engine performs a large set of tests, named "Rules", on the message, and after a few seconds returns a spam score, along with a list of rules which failed, sorted by relevance (each failed rule has its own score, so that you can easily see how much each problem is contributing to the global score). Please note that, while hundreds of tests are performed, only failed ones are shown (some of them may return a "0.0" score even if they failed, according to SpamAssassin engine current settings).
How to interpret results
To put it simply: high score = bad, low score = good! The overall score is the sum of the single tests scores. Failed rules are sorted by relevance; you should try to correct the problems generating a higher score first, then check the message again until you reach a good overall score (it doesn't have to be zero: obtaining a "Good" performance is enough). As a general rule, you should not worry about tests which are returning a low spam score (0.2 or lower).
Messages containing images receive a bad score with default settings; on real mail servers, rules are usually set so that images do not necessarily trigger high spam scores (see "Important notice" above).
Most of the tests are quite easy to understand even if you just have a basic knowledge of HTML: look in the "Reason" column, the text should describe which problem in your message lead to the failure of that particular rule. Some tests are more complex; if you can't understand what the "reason" means please refer to SpamAssassin official documentation: The column named "Rule" tells you the "official" name of the rule, so that you can precisely investigate SpamAssassin documentation (we suggest that you search for the rule's name).

Important notice
When you send out your mailing, the spam score calculated by the recipient's mailserver will be different than the one you calculated with MailingCheck: that's because each ISP has its own way of configuring antispam filters - and SpamAssassin is not the only antispam filter around. Furthermore, the quality of your SMTP service will be relevant for your message's spam score (sending from your local Windows SMTP service or through open relays - or through server known for being used by spammers - may increases the chance that it is flagged as spam).
Consider MailCheck as "the average filter", with very conservative default settings - if something is trapped by MailCheck, it is very likely to be trapped by "real world" servers too; if you get a good score with MailingCheck, and you send through a good SMTP service, you are likely to have no problems with your message delivery.

Other Recommended Spam Checker Tools:

Don't Let Your  
E-mail Newsletter End Up...
In your Customers' Junk Folder! 

Don't Get Mistaken for Spam Due to Email Content 


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