Serious question: Why does Yahoo's spam filter block only certain messages?

[elric]

As an example, Epic Cash spams me with a ton of emails promoting their stuff.

Almost all of Epic Cash's messages get through Yahoo's spam filters. Even stuff that should be easy to flag, like duplicate messages getting sent to me.

Max Cash also spams me with info about their programs, but the Yahoo Mail system automatically routes all maxcash messages into my Bulk Email folder.

So why is this?

Is it just that you need to know someone at Yahoo?

Or is there a trick to it? Does Yahoo offer guaranteed delivery of emails?

Anybody know?

[RK]

You should be able to easily block email based on sender and add custom rules. If not, just get a server side spam filter.

[elric]

Originally posted by RK
You should be able to easily block email based on sender and add custom rules. If not, just get a server side spam filter.

I know how to block spam using my own rules, but I'm curious about how certain messages always seem to get through.

Have you ever looked in your Bulk Email folder? Sometimes Yahoo filters out messages that are not spam...

But in this case it's two sets of messages that should get filtered out, if only because they are both filled with porn terms.

So why the difference?

[soldierdog]

Please forgive my flare for the obvious if you already are aware of the following.

There are so many possiblities of why this might happen. Max may be mass mailing off of the same IP block and thus get put into the bulk filter. The IP's for Epic may be new, it may also be the way the text and images interact on the html page. The number of images, the domain the images are linked to may have flagged words. The % of html vs text in the message. The color of the text, whether there is Rot13 in the message, has ReverseDNS been setup correctly, words in the subject line, wording like "unsubscribe", any variables being passed such like http://www.whatever.com/?variable=test etc. etc. etc.

These things are all scored and tallied for a final count that determines whether or not you end up in the bulk filter. It was interesting working against the Baysian Filters Hotmail put in place. It is like working against a boa constrictor if your sending in legit mail from a legit closed looped system.

Do an nslookup and throw the ip's into spamhaus and some other DNS blacklist sites.

Hope this helps. If you really need to know, send me the two messages and I may be able to tell from the way the creatives were done. If its not the creatives its a network issue.

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