Spam Automatic white listing

Automatic white listing sound like a great idea. As with a lot of these great ideas there is a catch to it. Several Spam filter users noticed that the effectiveness of the Spam filter suffers considerable the longer they use white listing. After some research it stated making sense.

The white listing for mail filters is based on the logic that if a person sends an email the person in general will accept mail from that recipient. By collecting these TO addresses from outgoing mail exclusion database can be generated.

The whitelisting theory: This allows the use a more aggressive Spam checking, simply because all your customers /friends and relatives are excluded once you have them an e-mail. However the implementation is often problematic.

What are the pitfalls of automatic whitelisting?

1, Auto responders: John is on his long awaited vacation enjoying the great outdoors. No phone, no Laptop, no email. He does not want to upset anybody so he sets his outlook to reply to every message he get. Telling them he will be back Monday 2 weeks from now. The automated reply does not differentiate between Spam and good email and the automatic white listing adds it all to the exclude table.

2. Read receipts: Another features used by spamers. This one really hurts. It's a very good way to make their "A" list of any spamer and mailing list peddler. .. …And you guessed right you're receipt just opened the door for them.

3. Uneducated users: Yes they are a white list enemy. You tell them a hundred times and some still do it.. They click on the "un-subscribe" over and over again and with every click your Spam filter looks more like Swiss Cheese.

How to use the White listing feature in XWall

Make sure that your outgoing mail goes through XWall. I had a few call from users claiming the XWall white listing did not work. In every case the mail did not go out through XWall therefor XWall could not gather the e-mail address of the recipient.

Start your XWall admin, go to view -> option -> Exclude white list and check the flag

Go to Flags check the Return receipt and DSN flags

Remove Return-Receipt-To: for
If checked, XWall removes the Return-Receipt-To: line from the message.

Return-Receipts are also known as Read-Receipt or Delivery-Receipts and are generated by the Exchange server or the client when a messages is read or delivered and the sender of the message has requested it.

Remove DSN SUCCESS flag
If checked, XWall clears the DSN SUCCESS flag at the SMTP protocol level.

The DSN SUCCESS is also known as Delivery-Receipts and are generated by the Exchange server or the client when a messages is delivered and the sender of the message has requested it.

What's in the Automatic white list table

You can edit AdrOWL-A.dat with an editor like Notepad and remove or add e-mail address.
However, you need to stop XWall while you are doing this and when XWall starts up, it will create a new AdrOWL-B.dat from AdrOWL-A.dat. Depending on the size of your AdrOWL-A.dat, this may take some time.

Summary

Automatic white listing may looked better a few moments ago. It is very attractive to many companies to ensure they can communicate with their clients and vendor. XWall does provide the tools to setup a well performing white listing system.. You can strip the read receipt. A serious talk may stop the auto responders and makes users reconsider. Study the situation. Keep an eye on the effectiveness of your Spam filters. If your Spam ratio on the weekend* is going down you may want to start investigating. Use ESAT to evaluate your Spam situation.

* It's assumed that over the weekend almost all email to business is Spam.