spam emails

[max]

I didn't know what was meant by spam until christmas just gone. I made the mistake of sending web email - christmas cards. There were some really good animated ones. However, soon after, I got a lot of unwanted emails from the card companies and then dozens from other unconnected companies. Thankfully yahoo do sort them as incoming bulk so they don't get mixed up with personal ones. I still have to delete and send them to Yahoo as spam and these are as many as 100 sometimes 200 a day. Is there anything one can do to stop them or is this a world wide prob for everybody?

[Iconoclast]

You should worry less about the spam you're getting and more about all your p*ssed off friends who will now be getting just as much spam as you are. eGreetings are a tool of the devil.

[max]

oh

[evildave]

Some internet service providers provide back-end spam filtering. I've had the same email address for ten years. I get a few spams a week, and about a thousand spam messages get caught in the spam filter.

Unfortunately, the spam filter is imperfect; it lets a few through, and occasionally catches some email that shouldn't have been caught. Usually these "caught" ones end up piling up in a web-mail box that you can visit and browse. I've taken to usually flushing the impound box without review.

[SilentBob]

Try Mailwasher (http://www.mailwasher.net/).

I've been using it for a while now and it's really good. Plus - it's free!

[Psi Baba]

I've recently thought of a very nearly perfect spam filter. All you need do is filter out any message containing strings of characters that are not recognizable words and/or strings of four or more consecutive consonants. I figure this would eliminate about 95% of all spam (this also relates to why I firmly believe that spam is not a legitimate marketing tool, but nothing more than gratuitous and malicious vandalism, but that's another whole issue). And there would be no worry of filtering legitimate messages.

Does anyone know of a way to construct an algorithm to filter messages this way?

[evildave]

Actually, about 60% of them claim to come from some foreign address. If I say I only want .org;.com;.net emails, and the filter gets a connection from a .kr or a .de or a .ru, or whatever, it should simply return that mine is an invalid email address. About half of them used to come from forged "free" email address sites, such as yahoo or hotmail, but now foreign email addresses are in vogue.

Nearly 100% of spam used to be BCC:d to me. The most effective simple home filter I ever did was to simply look at the "TO:" and "CC:" header, and toss the mail into the SPAM box if it was not addressed to me. Spammers have since generally stopped abusing BCC because this became pretty much a universal filter. So, BCC isn't very useful anymore, thanks to the spammers. This is much lower percentage now, but your email is still likely to be trashed for being BCC:d to you.

A "Bayesian" filter seems to work pretty well for now. This sort of filter accumulates keywords with a probability for being spammy. The more high probability keywords, the more likely it is spam. Then you simply set a cut-off level for being "spam". Of course, clever spammers have begun padding their spam with "regular" text, like "hey! I haven't (random typo) heard from you in a long time!..." for a few sentenses, with a few more typos, and then "Look at this cool link! ..." Of course, this eats away at filters. Soon it will be nearly impossible to send a web link to someone without your mail getting impounded, thanks again to spammers.

This site has a lot of interesting spam filter information and links to more.
http://www.paulgraham.com/better.html

Really, the spam filtering needs to be done on the mail server its self. Usually, it's a secondary step to filter the already-received email in the database. When the mail server actually accepts the connection, it knows exactly what IP address it's communicating with. It needs to do an nslookup on the IP address and compare that to the (Always! 100%) forged "from" email address, then reject the mail outright. Then if the site is kosher, it needs to ask the other mail server if that address is valid, and (again) reject it if that site doesn't recognize it.

Then there's the "black hole" list of known naughty mail servers. If your site's IP ends up on a black hole list, all your mail gets deleted by sites that subscribe to that list. The quickest way to end up on that list is to leave your mail server enabled to "relay" mail, since this is the first thing spammers look for, to exploit. They'll tie up your server's bandwidth infinitely by sending letter after letter with a thousand recipients each through your mail relay. Typically, your upload bandwidth is lower than your download, so each spam email consumes a LOT more resources to process than to receive. Until your server is utterly unable to send any of your own mail, and perhaps not able to do anything because it's so full of spam in the outgoing queue.

Yes, being able to send email with your notebook with your favorite mail client from another ISP connection would be nice, but that's what spammers also ruined, and why most ISPs have a seperate web front-end to their email, instead.

[Interesting Ian]

Originally posted by max
I didn't know what was meant by spam until christmas just gone. I made the mistake of sending web email - christmas cards. There were some really good animated ones. However, soon after, I got a lot of unwanted emails from the card companies and then dozens from other unconnected companies. Thankfully yahoo do sort them as incoming bulk so they don't get mixed up with personal ones. I still have to delete and send them to Yahoo as spam and these are as many as 100 sometimes 200 a day. Is there anything one can do to stop them or is this a world wide prob for everybody?

Hi Max,

Try always to avoid giving your email address out on the net. Give a false one if possible. If a real one is required use a "throw-away" email address rather than your main address so that once you start getting loads of spam you can simply delete the address. If you go in newsgroups then you need to ensure that when setting up your account you spoil your email address (eg I think I use interesting.ianDELETEME@ntlworld.com)

That way people will still be able to contact you, but any bots which comb the newsgroups to collect email addresses for spam purposes won't be able to spam you.

Come to think of it the poster Titus Rivas sent me a xmas card by email and I sent him one back. Not getting a load of spam though. Can't remember what I did, if anything, to prevent it. Of course I used a throwaway email address. Actually I've had my throw away address for about 2 years, and given it out on loads of forms on the net, and still scarcely get any spam on it! :)

[max]

Thanks all. I recently noticed that Yahoo (my email address) have a 'spam' box to click on and they delete,use the info and then block that email address in future. After following their instructions I haven't received any bulk spam or individual emails for some days. I think maybe Yahoo's filter is efficient.:)

[Bottle or the Gun]

Originally posted by Psi Baba
I've recently thought of a very nearly perfect spam filter. All you need do is filter out any message containing strings of characters that are not recognizable words and/or strings of four or more consecutive consonants. I figure this would eliminate about 95% of all spam (this also relates to why I firmly believe that spam is not a legitimate marketing tool, but nothing more than gratuitous and malicious vandalism, but that's another whole issue). And there would be no worry of filtering legitimate messages.

MS Outlook Rules doesn't do a bad job of filtering by moving e-mails containing certain words to whatever folder you want, but spammers have taken to putting the text in their message in an image format, so word filters won't catch it.

[alfaniner]

I heard of someone that uses "FF0000" as a filter. This catches anything that is printed in red text, which is very rarely sent by a valid sender.

I couldn't figure out how to do it in my Outlook Express. Apparently I have to actually download the message (from a Hotmail address) rather than just the header in order for the filters to work.

And no, I'm not changing to something else.

[evildave]

Switch to an ISP (other than A-O-Hell) that filters SPAM on the back end. You will be much happier for it.


The ultimate problem with trying to filter spam on your own email client is that YOU ALREADY DOWNLOADED IT. If it had a big, fat picture in it, or attachments, you spent time watching your email downloading status for extra time (times however many dozens of spam emails) while the mail came down from the server. This problem is especially bad in Outlook (& Outlook Express), with all of its many well-exploited security problems.