DIY Anti-Spam Tricks Kent Tong Deputy Director General of ECAM Manager of CPTTM Cyber-Lab
Do not publish your email address To fight spam, the most important thing is to not to publish your email address. What does it mean? Suppose that your company has a web page and on the page you tell people to contact you to place order or for inquiry:
Do not publish your email address
Do not publish your email address Then spammers can learn about your email in no time. They run some program that scans the web pages on the web, find emails address on the pages, follow the links and continue. In that case what can you do? If you remove the email, your potential customers cannot contact you. One solution is to write the email as:
Do not publish your email address
Do not publish your email address
Do not publish your email address Some more options: Contact me at ken_@macau.c_m.ne_ (fill "t" in the blank). Contact me at kent@macau.do-not-spamme.ctm.net.
Do not reply to spam What if you have already published your email address and have been receiving lots of spam? First of all, some junk mails seem to allow you to subscribe.
Do not reply to spam But if you do that, the only effect is that the spammer knows that you do exist and may send you more spam.
Do not reply to spam However, even if you don't reply to it, if the mail contains images, your computer will download the images from the spammer's website. By this way, the spammer still knows that you do exist. To solve this problem, you can configure Outlook Express to display all mails as plain text but no graphics.
Do not reply to spam
Filtering spam A better way is to filter spam. That is, install some software onto your computer. Whenever a mail is received, the software will check if it is spam. If yes, it will put it into the trash folder. Otherwise, it does nothing. Now, I'll introduce a very good spam filtering software utility called "POPFile".
Installing POPFile Go to http://popfile.sourceforge.net to download POPFile. Download the latest for Windows version. Unzip it and you will find a setup.exe file. Double click it. Choose Chinese. Keep clicking "Next".
Installing POPFile
Installing POPFile
Installing POPFile
Installing POPFile
Installing POPFile Now you need to tell POPFile how many "buckets" you need. By default, there are four buckets: spam, work, personal and other. It means that whenever POPFile receives a mail, it will try to classify it and drop it into one of these four buckets. For most of us, we only need two buckets: spam and work. So, let's tell POPFile to delete the personal bucket and other bucket.
Installing POPFile
Installing POPFile Say "Yes" to confirm.
Installing POPFile It can try to configure your existing mail clients (e.g., Outlook Express) to use POPFile. Click "OK" to let it do it. If Outlook Express is running, close it first.
Installing POPFile It detects my Outlook Express account. Check it to let POPFile configure it.
Installing POPFile It will let you know the changes that it will make. Just click "OK" to continue.
Installing POPFile It asks you whether it should start to run now? Just let it start by clicking "Next".
Installing POPFile It may take a while. Finally it should succeed.
Installing POPFile It will also offer to launch the "POPFile User Interface". Let it do it.
Installing POPFile
Installing POPFile Using this user interface you can configure POPFile. But at the moment you have nothing to configure. So, just close it. This will not POPFile, but just the POPFile user interface. You can also see that there is an octopus in the system tray. It means POPFile is running.
Using POPFile Now, open Outlook Express as you normally would. Suppose that now our engineer Raymond sends me a mail like:
Using POPFile
Using POPFile When I receive it, note that the subject says "[unclassified] ". It means POPFile doesn't know how to classify it.
Using POPFile This is normal. At the moment POPFile doesn't know what a spam email is like and what a work email is like. You have to teach it. So, double click the octopus. This will open the POPFile user interface again.
Using POPFile Choose "work" as the correct bucket and click "Re-classify". Now POPFile has become more smarter.
Using POPFile If someone sends you a spam, you need to tell POPFile that it is a spam.
Using POPFile
Using POPFile
Using POPFile
Using POPFile
Using POPFile POPFile will learn quickly how to classify the mails (e.g., in a day). It means you will rarely see [unclassified]. You will start seeing mails marked as [work] or [spam].
Using POPFile However, you need to know that POPFile is not perfect. Sometimes, it may mark a mail as [spam] but if you check the mail you may find that it is a work mail. Sometimes it is the opposite: it may mark a mail as [work] but if you check it you may find that it is just a spam. In either case, you should go to the POPFile user interface to reclassify it.
How accurate POPFile is How accurate POPFile is? In my case, it reached an accuracy about 85% in a couple of days (about 200 mails). Giving it a few more days the accuracy became about 94% (about 400 mails).
How accurate POPFile is
Deleting spam automatically Having mails marked as "[spam]" in the inbox is not very useful. We'd like to let Outlook Express automatically delete them.
Deleting spam automatically For the condition, check "Subject includes". Then click the link to define the text.
Deleting spam automatically Enter "[spam]" as the text.
Deleting spam automatically For the action, check "Delete". It means that if Outlook Express receives a mail, it will check if its subject includes the text "[spam]". If so, it will delete it.
Deleting spam automatically Now if you receive a spam, it will be automatically deleted. However, the mail is still marked as unread.
Deleting spam automatically We'd like Outlook Express to mark it as read, so that we don't need to bother with it. To do that, open the rules again. Edit the rule we created.
Deleting spam automatically For the action, check "Mark as read". Now all mails classified as spam will automatically and silently go into the trash folder.
Reviewing the trash folder regularly Of course, sometimes it can mis-classify a work mail as spam. So, you should regularly review the mails in the trash folder and recover the work mails.
Removing the [work] marker After creating the rule, in the inbox most mails will be marked as [work] (the rest few will be marked [unclassified]). So this marker is no longer useful. We can tell POPFile not to modify subject line if a mail is classified as work. Go to the POPFile user interface. Click the "Buckets" page and then turn off the subject modification for the work bucket.
Removing the [work] marker
References Email harvest FAQ: http://www.faqs.org/faqs/net-abuse-faq/harvest/ Munging address FAQ: http://www.faqs.org/faqs/net-abuse-faq/mungingaddress/ Spam FAQ: http://www.faqs.org/faqs/net-abusefaq/spam-faq/ Fooling spammers: http://www.nwfusion.com/newsletters/edu/2003/0 324ed1.html