Email Policy

The MTA on is surely the domain's busiest server. According to our logs and user reports, more than 90% of mail-related traffic is consumed by unsolicited bulk email and malware. Over time, I grew quite unhappy with this situation. To change things, few measures were undertaken to stop these unsolicited messages.

Unfortunately, as a side-effect, a few solicited messages fail to reach their destination every now and then. I am very aware of this and have decided to live with it, rather than to receive unsolicited ones. If you have tried to send a message to someone at this domain and failed, here are few reasons why, along with a few hints regarding what you can do about it.

Mail delivery on goes through the following three filtering steps:

Step 1: During the SMTP session with our MTA, the IP address of the peer is searched for in a list of bad peers. If found, the message is not accepted, whereever its origin, whatever its content.

Note: If your message fails to pass this test, you will likely receive a notice from your site's mailing software. If you receive a report about failed delivery which says that our MTA didn't accept the message from your MTA's address, then you can contact the recipient by other means and have him except your MTA's address from this test.

Step 2: A general filter scans the message and looks for signs which are typical for unsolicited bulk mail. If such signs are found, the message is delivered to /dev/null. No questions asked, no answers given, no prisoners taken.

Note: If your message fails to pass this test, it will be deleted. Neither you nor the recipient will be notified about this. In this case, your message has few attributes our filter system takes as typical for spam. Resending your message in plain-text instead of HTML helps. Not attaching malware helps as well.

Step 3: The content of the message is scanned by a bayesian classifier, using the recipient's individual training data. If the message is classified as unsolicited, it is delivered to a special folder instead of recipient's mailbox.

Note: If your message fails to pass this test, it will probably go unnoticed, as users check their folder designated for spam close to never. If the message remains in that folder, the bayesian classifier software will reread it when it updates its database. This will confirm the message as spam, making sure that other similar messages fail to pass this test as well. Watching your language when composing the message will make sure that this doesn't happen. You probably receive spam as well, you know how it looks like. If we liked its looks, it would never have started bothering us, so try to send mail which is totally different to that.

If the message passes all three tests, it will be delivered to recipient's mailbox. If you are a spammer, congratulations, you have made it through. If you are an honest peer, please accept my apologies for the inconvenience these tests might have caused you.

Postmaster, 20. December 2003

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