Automated Email Submission System - Spam Weight

Question

Good afternoon,

We have developed a system that sends automatic letters to our customers using pdf attachments. Some of the clients mentioned that emails are selected as spam, and IT guys say that mail has a high degree of spam protection.

As mentioned, the headers from your system include 2.0 TotalSpamWeight, while it should be <0.

What should I look for to change this?

I am using Delphi 2010, indy 10 tidSMtp component to create letters. The body is in html, and the images in the body are outside.

Please inform

Answer 1

Ask the IT guys what rules are running.

Answer 2

It may not be Delphi related. Is the email sender from the same domain that sends the email? You can ask your client to send you the headers of the message they received as spam, and then examine these headers. TotalSpamWeight is calculated using some anti-spam tool, possibly from SmarterTools or SpamAssassin, and can only be associated with some keywords in your letter. For example, the word "Viagra" will cause a lot of anti-spam filters, even if you mention it in such an innocent way as I just did ...
Oh, these external links may be what triggered them! Many spammers use them to track emails and, as a rule, add a special code to each image that confirms whether someone’s email address is real or not. If the image is uploaded, they have confirmed the email address. If not ... Well, this trick is why external images will cause emails as spam. Especially in combination with some other keywords.

Answer 3

There are many factors that are commonly used to determine spam weight, and they vary from system to system. It is difficult to say without knowing which system performs the classification and the factors that the system uses, and an example message.

However, the easiest way to look for a developer to check is the reliability of the message. If you have an HTML message - is it built correctly? Is there a text alternative part of the message? Is the content type correct? Having a poorly designed message can usually add weight to spam.

Also look for probable flags, such as inline javascript inside your message content ... which I would assume is a universal trigger. HTML letters should usually be composed using plain old HTML without a lot of bells and whistles.

One approach that you always need when developing email is to send the message to different systems such as GMail, Yahoo, HotMail .. and see the message headers yourself. Inside message headers, there are usually some tips to help you determine why it has been flagged as possible spam.

There are ways, as a rule, outside the control of the developer, how to reduce spam weight, and also about what you should know ... SPF records are probably the most common quick add-on that your IT guys should do, then domain keys, white lists, and many third parties who want to take your money to confirm your messages.

Good luck

Answer 4

What would I do: install a spam filter on your computer network and send letters to me. Then I could easily check the filter log files or other sources of filter information. With documentation on filter software, it should be easy to find the reason for the spam warning.

Perhaps there are even online services that you can use to check your mail using one or more popular spam filtering systems, just like online virus scanners.