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Spam Blocking Software

Help, the spammers are winning the battle

         

jdancing

6:02 pm on Apr 3, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



I am sure many webmasters are having the same problem.

If you run a web business, your email gets on just about every evil spam list out there. I have a spam blocker that I use for my personal email, which works fine because I can add my friends to a buddy list. But I am afraid it would block customer emails if I used it with my web business emails. I need something more robust.

I searched the web, and I can't seem to find anything that is the overwhelming choice. Please PM me your favorite spam blockers.

Thanks,

John

Robino

6:08 pm on Apr 3, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member




You could try using a contact form instead of a mailto link. Or you could js your mailto link.

I do both and I don't receive much spam.

Mr Bo Jangles

6:10 pm on Apr 3, 2004 (gmt 0)

10+ Year Member



I read on this forum someone else raving about SpamBayes and I went and searched for it and downloaded it.
It is an opensource type project, and it is free, and it works brilliantly.
It installed flawlessly for me.

digitalv

6:24 pm on Apr 3, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



Spam software will always do one of two things: It will catch EVERY spam and a few messages that you WANT to receive from customers, or it will catch "some" spam and let your customers e-mail you.

Most of them are based on rules/keywords within the messages, not sources, so depending on how your clients word things if the spam blocker thinks it's an advertisement its going to drop it.

I do two things to prevent SPAM:

(1) Never put an e-mail address on your website. Use a form. DON'T use a form that has a "hidden" field with the email address in it, that's just as bad as having the mail address on the page. Embed the recipient addresses in your ASP/Perl/PHP/Whatever code.

(2) This is by far the best method for me. Set up a "catch all" account at your domain. So someone could send mail to "anything"@yourdomain.com and it gets to you. Then what you do is whenever you register for a site that requires your e-mail, put in the SITE NAME @yourdomain.com

Example: webmasterworld@yourdomain.com

Now whenever you get SPAM, just look and see who the recipient is - you'll instantly know which website you registered at sold-out your e-mail address. Then you can make message rules on your mail server to delete all future mail sent to that address.

bird

6:38 pm on Apr 3, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



Spam software will always do one of two things: It will catch EVERY spam and a few messages that you WANT to receive from customers, or it will catch "some" spam and let your customers e-mail you.

Most of them are based on rules/keywords within the messages, not sources, so depending on how your clients word things if the spam blocker thinks it's an advertisement its going to drop it.

Smart filters work differently, and Spambayes is one of the smarter ones.
You'll have to train it on the specific spam/ham you receive, so that it will learn how your customers typically phrase things. A filter that doesn't adapt to your specific situation isn't a smart filter.

It will then sort the mail into three buckets, and you can configure where you want the boundaries to be, and what happens with each bucket.

The obvious (to the filter) spam is marked as such, and I've only seen false positives in there from one specific (automatic) sender, which would be easy to fix on their end.
The obvious (to the filter) ham is normally placed in your inbox as before. I receive hundreds of spams each day, and once a week or so I'll see one slip through there, which most of the time is in an unusual language so it's not covered by the training of the filter.

And then, the smart filter will have an "unsure" bucket, where it places anything that it doesn't consider obvious. What you'll find there are new forms of spam, bounces from spam that was sent faking your domain in the sender, and once in a while a legitimate message that uses "spammy language". It is a good idea to use those messages to refine the training of the filter.

In addition to that, you can use a variety of RBL type lists, but I've seen significantly more false positives as a result from that than from Spambayes.

PCInk

7:49 pm on Apr 3, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member Top Contributors Of The Month



Most mail programs allow folders and mail rules. Setting some of these up by hand should help. Instead of deleting suspected spam automatically, you can move it to a spam folder, which can be checked every so often.

ara818

11:06 pm on Apr 3, 2004 (gmt 0)

10+ Year Member



Spam Assassin is probably the most popular tool used on the server-side for spam filtering. It uses a variety of techniques for spam filtering is very configuratble and very extensible. It can easily is integrated into most MTAs so that the spam filtering process is basically invisible to you.

check [spamassassin.org...] for more details.

Zaphod Beeblebrox

10:17 am on Apr 4, 2004 (gmt 0)

10+ Year Member



I installed SpamBayes on dec 7th 2003. Since then, it has successfuly detected 4267 spam messages, the bulk of which at once, and some it placed in the 'Junk Suspect' folder first.

Only 3 non-spam messages have been dubbed suspect, and only 1 spam message wasn't detected.

Seems like a good track record.

vrtlw

10:58 am on Apr 4, 2004 (gmt 0)

10+ Year Member



Personally, I use SpamAssassin (a bayesian filter primarily) to identify possible incoming email as spam. Any email it identified as possibly being spam I forward to a challenge/response system (there are plenty out there). After training the bayesian filter against spam/ham I very rarely get an email that is mis-identified as spam. Additionally I have yet to find a potential business opportunity that has been forwarded to the challenge/response sytstem, normally the ones that go through are mailing lists that I signed up for many moons ago and had forgotten about.

bird

12:20 pm on Apr 4, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



Any email it identified as possibly being spam I forward to a challenge/response system

Since most spam comes with a faked sender address nowadays, you're harrassing an innocent person for every spam you receive. You're effectively doubling the amount of unwanted mail in circulation.

This isn't generally considered a good idea.

ControlEngineer

1:27 pm on Apr 4, 2004 (gmt 0)

10+ Year Member



Any email it identified as possibly being spam I forward to a challenge/response system

These challenge/response systems are getting to be a problem. I get a message or two a day from them due to spoofing. People who pay to download an eBook from my site get an automatated receipt that also contains information about how to get a free update. Those that use challenge/response do not get the message.

Since I also market my engineering services through my web site I cannot use c/r; most people will not respond to the challenge but will go elsewhere.

In fact, if you do business or advertise your products or services over the web, a challenge/response system is the best way to discourage customers.

Another good way to discourage customers is to list your e-mail address with "nospam" inserted and instructions to remove that. You should make it easy for potential customers my using a working mailto: link for your e-mail. Spammers have software that will automatically remove the nospam and other modifications to e-mail addresses. I recently received some spam advertising spamming services that will automatically respond to challenge/response systems.

dhatz

2:21 pm on Apr 4, 2004 (gmt 0)

10+ Year Member



Unfortunately, the PRIMARY thing to do is to try to evade getting on spammers' lists.

This is impossible if you're a real operation communicating with 1000s of potential customers per month, as once one of those correspondents PC is hi-jacked, your email is harvested by the spammers.

I just checked and two old email addresses (which we used in the mid-90s and I've removed since 1998 to create a "user unknown" 550 error by the MTA, yet references to them remain in many webpages around the world), receive and reject over 2500-3000 spam mails PER DAY, each one of them.

I can't imagine what a larger organisation might be getting. Our scale is very small in my opinion. And the example i mentioned was for non-profit things, i.e. it costs me a lot of time to deal with the side-effects of providing a free service to the Internet community. "No good deed goes unpunished" :-(

If one has the capability to operate and have FULL CONTROL over their own mailservers, I would recommend a combination of RBL and SpamAssasin. The latter is suppsed to implement support for SPF and other sender authentication technologies, like those proposed by Yahoo and Microsoft.

Unfortunately email and Web spammers are making things a lot more painful, complicated, costly, time-consuming and difficult for legitimate e-biz.

jdancing

1:37 am on Apr 5, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



I use all the java script encoding and do everything possible to hide my email but with my business I have to give my email out to many unknown members so it's hard to hide and even if possible, it's too late to anything but somehow block these messages.

I didn't mind the old sales pitches, but now I get hard core porn, pictures and all. You know the ones, they start as a blue link box and expand into a full blown picture. Not good if the kids are playing in my office.

What about those services that require a reply to a verification email before letting an email pass through. Seems liks some legit customers could get scared away.

ControlEngineer

4:07 am on Apr 5, 2004 (gmt 0)

10+ Year Member



What about those services that require a reply to a verification email before letting an email pass through. Seems liks some legit customers could get scared away.

See my comment about challenge/response in msg#11.

Not only do potential customers get scared off (not always scared off, but they send an e-mail at one time and don't get the response until they check their e-mail, perhaps the next day). Also there are so many automatic systems--alerts from my bank, reports from business services (Adwords and Adsense, etc.), order and shipment confirmations or delay information, hotel and airline confirmations, etc. Challenge/response will eliminate them unless we know ahead of time the exact e-mail address they will be sent from.

I think that laws stronger than CAN-SPAM and tough enforcement of the laws is the only answer. That won't completely stop it but it should reduce the amount without making internet communications more difficult for legitimate non-spam use.

varya

4:15 am on Apr 5, 2004 (gmt 0)

10+ Year Member



When I started having spam with graphic pictures showing in my mail, I did two things.

1. I turned off html email. I receive everything in plain text now. I also did this because I didn't want embedded beacons triggering whether or not I'd opened the mail.

2. I started using Mailwasher to pre-screen my mail.

I no longer use Mailwasher, as my ISP offers Postini spam screening. Very little spam gets through to my computer anymore.

edit_g

4:23 am on Apr 5, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



I'm a bit perplexed regarding this. I have four email accounts.

I use one for work.
I have one personal account.
I have one hotmail (soon to be Gmail :)).
A second hotmail account.

I use the work email for communicating with work contacts and I never get any spam.

I use the personal one to communicate with friends, relatives etc. I never get any spam - this email has no spam filtering and is available on a public website.

I use the first hotmail one to sign up for legitimatenewsletters, mailing lists even for webmasterworld - any webpage which requires my email address gets this email address. I get about 1 spam a day.

I use the second one for signing up to online newspapers, public relations updates and competitors newsletters etc - anything where I can't be at least 75% sure of my email being distributed. I get around 5 spams a day.

Why am I not getting flooded with spam? I know that it is a searious problem for some but I just don't know why I'm not being affected.

Scooter24

9:26 am on Apr 5, 2004 (gmt 0)

10+ Year Member Top Contributors Of The Month



I am sure many webmasters are having the same problem.
If you run a web business, your email gets on just about every evil spam list out there. I have a spam blocker that I use for my personal email, which works fine because I can add my friends to a buddy list. But I am afraid it would block customer emails if I used it with my web business emails. I need something more robust.

I searched the web, and I can't seem to find anything that is the overwhelming choice. Please PM me your favorite spam blockers.

A year and a half ago I installed several bad bot traps on my site (hidden links with scripts which would add a deny from xx.xx.xx.xx line to .htaccess). Since then all my spam problems have disappeared, even if my email address is displayed prominently with a mailto: link in the contact page. Basically the traps block all email harvesting bots.

Zaphod Beeblebrox

9:38 am on Apr 5, 2004 (gmt 0)

10+ Year Member



Unfortunately, the PRIMARY thing to do is to try to evade getting on spammers' lists.

Even more unfortunately, if you have an email address that's been around since 1995 there's simply no avoiding those lists... ;-)

ControlEngineer

2:51 pm on Apr 5, 2004 (gmt 0)

10+ Year Member



Why am I not getting flooded with spam? I know that it is a searious problem for some but I just don't know why I'm not being affected.

Count your blessings. I guess in your case there is no way for spammers to get your address. For many people that is the case. However, for me (and many others) there is no way to keep the e-mail address from spammers.

On a site with information about my engineering consulting services I have my e-mail address, as well as snail mail and business phone number. I do get work (typically contracts for several months work) by e-mail. Sometimes the work comes from people who I worked with years ago but they did not have my contact information until they found the web site.

I also participate in work related newsgroups and forums that (unlike this one) allows e-mail addresses either as a part of the forum structure or as part of the signature line. I have received business this way.

I am a director of an international organization for control engineering. My e-mail address is listed on their web site. It is required that a member of the organization be able to e-mail me if he has any need (very few do, but it has to be possible).

I just had to send a message to a lawyer whom I did not know and have never had contact with. His e-mail address is listed on the firm's web page. I assume that the time reading my message will be billed to his client.

I average about 50 spams per day. Others I work with in similar situations get about the same amount or more.

I think strong laws (better than CAN-SPAM) and some real effort in enforcement is the only way to reduce spam. It won't be 100%, but it can reduce the problem.

richlowe

3:30 pm on Apr 5, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



The answer is get a spamcop account. It will give you complete control over spam. Messages that trigger the filters go to a held folder where you can scan them and add them to the whitelist if valid.

spamcop. Spamcop. Spamcop.

It's simple.
Richard

Brett_Tabke

4:10 pm on Apr 5, 2004 (gmt 0)

WebmasterWorld Administrator 10+ Year Member Top Contributors Of The Month



Outlook 2003. I've eliminated spam almost 100%

(believe me - I am on every spammers list on the net)... 3k rejects a day out of 3.5-4k in)

dhatz

5:32 pm on Apr 5, 2004 (gmt 0)

10+ Year Member



I think strong laws (better than CAN-SPAM) and some real effort in enforcement is the only way to reduce spam. It won't be 100%, but it can reduce the problem.

Most spam nowadays is being sent from hijacked PCs all over the world (about 500k PCs by industry estimates), belonging to unsuspecting ordinary users in USA and Europe.

One could "follow the money", ie go after the people who stand to gain by spamming activities. But how can you be SURE and PROVE they actually ordered the mass-mail? e.g. if tomorrow someone sends 40million email messages via 5000 different IPs-PCs scattered all over the world, advertising this site, can we be certain that the WW owner ordered it and not e.g. a competitor trying to damage his reputation?

A year and a half ago I installed several bad bot traps on my site (hidden links with scripts which would add a deny from xx.xx.xx.xx line to .htaccess). Since then all my spam problems have disappeared, even if my email address is displayed prominently with a mailto: link in the contact page. Basically the traps block all email harvesting bots.

See point above. What if spammers do distributed harvesting of emails? Will you have a htaccess file blocking 1000s of IPs? What about performance?

Wrt email harvesting bots: Lately I've come across (never ran any of it) Win32 software that will let you "collect emails from your documents on your PC and web addresses" (a legitimate task for a small office that wants to organise contact lists of customers) that's given away FREE. I would suspect that such sw talks back to its creators and gives them your list.

We're reaching a point of mass-hysteria wrt spam and I understand it only too well. But it's VERY COUNTERPRODUCTIVE in doing business. I just read the mailing-list suggestions of spamcop at

[spamcop.net ]

How many small or medium sized businesses outside the IT sector have the resources to have such a "secure opt-in mailing list facility"? Only fairly recently the list software implemented such functions.

Outlook 2003. I've eliminated spam almost 100%

But what if one needs to access email outside the office? (home/on the road)?

engine

5:48 pm on Apr 5, 2004 (gmt 0)

WebmasterWorld Administrator 10+ Year Member Top Contributors Of The Month



Whatever you do, the torrent of nonsence will keep coming. Just choose your system carefully.

At the moment, spamcop is struggling. The spoofed e-mail addresses are getting reported by those that don't understand what's going on and legitimate e-mail is getting blocked.
I have recently taken spamcop off my list of relays to check against.

By using a combination of mailwasher (checking third party relays and filters), bayesian filters and e-mail client filtering, we've just about eliminated all but a few spam messages and worms that hit the mailbox before they are distributed by our system (I think only one got through in the last three months).

One last point, whatver system you're using, don't respond or bounce any e-mails back to the spammer. It only proved you have a live address.

john_k

5:57 pm on Apr 5, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



One last point, whatver system you're using, don't respond or bounce any e-mails back to the spammer. It only proved you have a live address.

I definitely agree with that!

And (previously) I would always add that your system should simply delete the spam. All of a sudden, however, I am wondering if messages determined to be spam shouldn't be forwarded on to maybe... my favorite senator.

"Dear Senator <your favorite senator>, I'm swamped with SPAM email. I am forwarding another one to you. PLEASE HELP! Please use your position to follow the money trail! Thank you!"

yeah - yeah - I know, what can one government do when it is a global issue. And people who do this will probably be the first ones actually convicted under the CAN-SPAM act. Just wishful thinking.

ControlEngineer

9:19 pm on Apr 5, 2004 (gmt 0)

10+ Year Member



...spam shouldn't be forwarded on to maybe... my favorite senator.

I've done that. I usually forward my spam to uce@ftc.gov. The Federal Trade Commission actually requests that spam be forwarded to that address. It won't fill up anybodies in-box; I think it goes into a computer database for counting and analysis. (This is for US based readers).

ControlEngineer

9:38 pm on Apr 5, 2004 (gmt 0)

10+ Year Member



One could "follow the money", ie go after the people who stand to gain by spamming activities. But how can you be SURE and PROVE they actually ordered the mass-mail? e.g. if tomorrow someone sends 40million email messages via 5000 different IPs-PCs scattered all over the world, advertising this site, can we be certain that the WW owner ordered it and not e.g. a competitor trying to damage his reputation?

It takes good, old fashioned, detective work. It is of no real use to track the e-mail; too much is from hi-jacked computers or people who change ISPs almost daily. However, if someone orders some "Viagra" or body part growth stuff, they have to enter a credit card number and the material is delivered (if it is delivered) through some means (typically not the post office to avoid Postal Inspector involvement.) Then the sender is tracked using credit card information and back tracing on the delivery. It takes work and money, but it can be done. Almost all the enforcement has been private civil actions.

For example, AOL has siezed an expensive sports car belonging to one spammer and will give it away on-line. They say that nothing scares the bad guys like the thought of losing their toys. Government law enforcement would work better because only the government agencies have subpoena, to obtain search warrents, wiretaps, etc. Some law enforcement agencies have sets of credit cards specifically used for investigations.

The U.S. Small Business Administration’s Office of Advocacy is looking out for the small businesses that do the spamming, however. They also took positions against junk fax regulations.(our tax dollars at work).

If the flow of money, typically though credit cards, to spammers is stopped, spammers can be stopped.

garyoa1

2:47 am on Apr 7, 2004 (gmt 0)

10+ Year Member



Well, since we have an older domain (circa 1995) we get inundated with garbage. Used to love the multiple forwarding to all our users. The duplication meant that it was virtually impossible to misplace a sales lead. And the catchall accounts to grab the typo's so the user won't have to resend, or worse, not contact us at all. Not to mention just adding an email address whenever we had a need.

Thing of the past. Forced to eliminate the catchall. Had to set pop accounts for all users and eliminated about 20 email accounts and send everything else to dev null. Still, with all this we get nearly 1000 a day. A few years ago when we were only getting 50 or 60 a day we spent an hour or two a day tracking it and reporting it. Finally had to give up. Just got inundated. Now just run mailwasher and probably still spend an hour a day just deleting garbage. Hoping we didn't screw up and dump a good one by mistake.

And now, they don't seem to be satsified with this, they are starting to hit our bulletin boards. Tracking those IP's runs through a half dozen countries before it comes to a dead end. And even when you do track to a legitimate ISP, the bigger ones couldn't care less about bulletin boards. Don't even respond to the complaint.

This may be of some interest... [hostedscripts.com...]
No idea if it really works, but it's a shot. Interesting concept.

Brett_Tabke

2:57 am on Apr 7, 2004 (gmt 0)

WebmasterWorld Administrator 10+ Year Member Top Contributors Of The Month



> But what if one needs to access email
> outside the office? (home/on the road)?

Funny you should mention that. Ever hear of ms's active sync? 1

1 it's a nightmare - me recommending a ms product!

HarryM

3:49 am on Apr 7, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



Most anti-spam software attempts to detect spam and route it to a seperate spam folder. I use Outlook Express and I take the opposite route by setting up seperate inboxes and creating message rules to route the stuff I want to the apropriate inbox. For example I have inboxes for family, subscribed mail, book retailers, ebay, site users, etc.

A big advantage is that it sorts my mail into categories so I can just check the inboxes I am interested in at that time. All the dodgy stuff stays in the main inbox and I can check through it at my leisure. If I find something legit I create a new rule so next time it gets routed appropriately.

It works pretty well at the moment, but I only get a few hundred emails a day so I might have to go to something different if it increases.

TheDoctor

8:47 am on Apr 7, 2004 (gmt 0)

WebmasterWorld Senior Member 10+ Year Member



I use TheBat!, which also has a built-in system for dealing with recognised mail. Running through the (these days, enormous amounts of) stuff left behind to check for non-spam messages is a short task.
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