Email Campaign detected as Spam

[duzoid]

Hi,

When I am sending mass emails to my customers using Campaigns, they tend to be detected as Spam by email clients (Outlook, Yahoo, Google...). This happens even when we are sending a few test emails from a campaign.

I am using SendMail and Apache.

I was wondering if someone had experienced the same problem, or if someone could give us some clues on how to workaround this problem.


Red hat - SugarSuite v3.5 - Apache

[stevec]

The best bet to help with this is to see the recipients spam scoring for your emails. IF they are receiving the emails - but having been marked as spam - then see if you can get the full headers for these emails as they will probably include the scoring and reasons for scoring which you can address.

[andybesy]

Hello,

The above poster's suggestion is a good one: if your message is being identified as spam by SpamAssassin then it is likely that the scoring details will be recorded within the headers. It would be useful to see them.

Some other hints include:

- Be sure to send your messages FROM an email addres that is on a valid, resolvable domain
- Be sure to use a real-name header alongside the email address
- Be sure you are not sending from a mail server on a dynamic IP address
- Be sure that the mail server you are sending from has a PTR record for its IP
- Be sure that the DNS name the PTR record points to resolves back that same IP
- Be sure that your mail server helo's as that same DNS name
- Be sure the IP of your mail server is not blacklisted
- Be sure any URL's in your message are not blacklisted
- Be sure your message content is not spammy. Avoid capitals and any obfuscation
- Be sure to include and hohnor unsubscribe links for any commercial messages

You would be surprised how many factors are taken in to consideration by spam filters. The above are just a few basic suggestions. If you have problems with AOL sign up for their feedback loop system. See postmaster.aol.com.

HTH, Andy

[duzoid]

Thanks for your suggestions.

I also received a spam analysis on a returned mail yesterday:

Content analysis details: (3.3 points, 3.0 required)

pts rule name description
---- ---------------------- --------------------------------------------------
0.2 REMOVE_PAGE URI: URL of page called "remove"
0.1 MPART_ALT_DIFF BODY: HTML and text parts are different
0.1 HTML_80_90 BODY: Message is 80% to 90% HTML
2.9 HTML_IMAGE_ONLY_12 BODY: HTML: images with 800-1200 bytes of words
0.0 BAYES_50 BODY: Bayesian spam probability is 40 to 60%
[score: 0.4388]
0.0 HTML_MESSAGE BODY: HTML included in message

The original message was not completely plain text, and may be unsafe to open with some email clients; in particular, it may contain a virus, or confirm that your address can receive spam. If you wish to view it, it may be safer to save it to a file and open it with an editor.

We are trying to send HTML emails with images and although they look nice, they probably get more rejections.

I'll now check the settings you were referring too.

Cheers,
Duzoid

[andybesy]

Hi there,

The default setting for SpamAssassin is to consider a message spam (and probably tag it as such) when it scores 5.0 or more. Of course the tag level can be changed by the server admin, or even on a per-user basis; that's just the default.

Looking at the scoring details (for this particular server) you can see that the significant factor was the amount of HTML in the message body in comparison to plain text:

2.9 HTML_IMAGE_ONLY_12 BODY: HTML: images with 800-1200 bytes of words

Including a plain text alternative would help. It can also be useful to embed images instead of linking to them online, but this has it's own disadvantages because each message would be much larger.

You would get away with a score of ~3.0 on most mail servers, but the likes of Yahoo, Google and AOL are special cases.

They handle so much email that they tend to rely more on SMTP level restrictions such as those I described previously than content filters like Spam Assassin. Running Spam Assassin on a message is very expensive in terms of server load. If you can't get mail in to a big ISP like this its likely you have some DNS config problem or a black-listing.

Let us know how you get on.

Andy