This page has been robot translated, sorry for typos if any. Original content here.

Three lines of protection from spam

It all began on the verge of centuries in 2000, at which time the editor of the cascading style sheets CssMagic was written. In the mailbox of the support of this program, which by the way, we thoughtlessly showed in all the forums also guest books, the number of advertising letters had exceeded the number of useful messages. The box was here bla bla bla abandoned, but the address of support in the body of the program is changed. And also just now, for curiosity, we looked that blah blah with him (with the old box) was going on. Well, of course, as you might guess, it is scored right up to the denial. Cleared it also measured the capacity of receipts: in the hundreds of letters a day. Absolutely all messages are spam. Well, it is even interesting - will it be possible to defeat this universal evil?

We set categorically also essentially the following goal: openly also unencrypted to report this dead address in several forums to also configure the work with the box in such a way so as not to receive spam in any way, but useful messages from strangers receive all the blah blah, but messages acquaintances to acquire in order to become. Judging by the neglect of the situation, deeply echeloned defense will be required. There are three points where it is allowed to destroy spam. This is an email program, anti-spam software and an email server. Consider it (the defense) in more detail.

The main zagdlyatny line. The free SpamPal program checks the mail against the lists of DNSBL servers very badly (especially bad ones are eliminated quite well, but at the same time, it’s not very clever spammers that cann’t hide their IP, or the nation is just stupid sending spam from the "fake" domain). The program adds the specified keyword to the message subject. The default is ** SPAM **. Let it remain so. Further, the mail customer is forced to deal with this message.
The second zagdlyatny line. We take the most powerful program in the universe for labor with mail. In my case, this is TheBat !, but the paint also tastes - you know, therefore, options are possible. For TheBat! The following manipulations have been done.
In the properties of the mailbox, we configure the work through SpamPal, for which we specify the POP server name localhost, but we will add a real POP server to the user name via a dog, for example: (this is the standard SpamPal setting).

To automatically delete spam messages without downloading, set the "Mailbox -> Mail Sorter Setup -> Selective Download" position. Here we create a rule that if there is a signal line ** SPAM ** in the "Subject" field, it will eliminate the message from the server.

It is clear that with this setting, letters that are mistaken for spam may well be caught. To visually fix this event, we enable the mail dispatcher: "Mailbox properties -> Mail management - Mail dispatcher - Automatically call upon each check." Today TheBat! He will illustrate that it has also come that he is going to delete without downloading from the server (there’s a way to make adjustments to his actions).
We try the work of the first pair of frontiers: for three days, 245 letters were received in a casket (238 of them are advertising content, the rest are mine from other mailboxes). The resulting bundle identified also deleted 195 letters. The initial target is not fully achieved, although there are some results all blah blah. Moving on. Today it is necessary to solve two problems: automatically finish off the remnants of spam is also the essence, to exclude the removal of not spam.
The third frontier is the most powerful. This is where server-side filtering resorts to help. We do so. In all forums, etc. we leave our address as For strength, it is allowed to explain to the forum users in PS that the NOSPAM expression must exist in the subject line of the message. Next, configure the filters. On the sample
Filter 1. All possible logins (or their fragments) of important senders from your address book are listed. Act - send a copy of the message somewhere. In my case, this is an SMS to a cell phone. When the filter is triggered, do not continue to apply other filters. Filter 2. If the topic contains the phrase "NOSPAM", then just do not continue to apply other filters.
Filter 3. If you eat @ in the "Recipient" field (that is, none of the first two filters worked), then send a copy of the message to a specialized (garbage) address without deleting the message itself. Continue to apply other filters. In principle, this filter is not particularly needed. Just for each adventure, we will save all automatically deleted correspondence in a special mailbox.
Filter 4. And finally, if in the field "Recipient" to eat @ (continue disassembling with suspected spam), then delete the message also automatically reply: "Your message was destroyed by the anti-spam security system. If you want the message to reach the addressee login @, then repeat your message, and include the key phrase NOSPAM in its subject in any convenient room. "

Setting filters on the sample

So. Scribbling a spammer robot. Approximately prkticheski always return address - linden. The phrase "NOSPAM" is unlikely to be in the subject. It is also very unlikely that the spammer's login will coincide with the logins of my "snow-white" list. As a result, a message will be sent to the false return address with a request to repeat the message. The spammer will have to contact you manually. Extremely unlikely.
The case is different. Scribbling a friend or forumchanin. A white list will work on the server, and a list of letters will appear in TheBat! The final decision - to accept or not these messages remains for the user, but SpamPal is also TheBat! they will do everything possible so that the necessary marks about downloading or deleting letters are already standing.
If all the blah blah what a clever robot has learned to break through the security, it is enough to replace the expression "NOSPAM" with any other security also at your service again.
Of course, all this is also allowed to be done only by means of the mailer, but eliminating 100 letters of spam, even without downloading, takes 3-8 minutes, plus viewing the message subject - the same number. So on the server side, doing all the dirty work is more convenient.
That is, in fact, everything. During the week of work with the described settings, we received only one instruction to study the next course of the English language, and the notes about its removal were in the dispatcher of letters even before the download. Not bad. What also everyone wants.