What effective options are there to combat spam?

Dr.sunil V August 18, 2014

What are effective options – both built in and webapps – to counter spam email?

  1. Ben S
    August 18, 2014 at 5:46 pm

    Oron already took a lot of what I was going to say. Overall, using a good email service is key. I use Gmail and get maybe three spam emails a month, if that. Most of the stuff that shows up in my Spam folder is ads from companies like Dell that I may have signed up for, not fake spots for Viagra and the usual junk like that.

    If you get spammed from a particular source over and over, consider setting up a filter like I told you about in another question.

    Be careful about where you give your email to. Don't give it out to stores or websites randomly unless they have a good reason for asking.

    • Sunil
      August 22, 2014 at 5:46 pm

      Thanks. Can a filter be set as Default Inbox / Main Inbox , instead of as folder?

  2. Oron J
    August 18, 2014 at 5:25 pm

    "Email" is the last word of your question, Dr! This is a huge question and one could probably run a week long course on it rather than give a short written answer, still...

    The first protection against spam is not to distribute your email address willy-nilly "in the open". For example, not posting it on forums etc. If you need to provide it in such a place, use a form that others willbe able to read, but a machine will not pick up (e.g. post a picture with your address, or write "dr.sunilV at gmail.com"). This will reduce the automated "harvesting" of your email address in the first place, but will not prevent it altogether.

    In a similar vein, if you need to provide your address to a website which you don't entirely trust (e.g. to register to a new site), use a disposable email address for the purpose (Outlook.com has an "alias" option for similar purposes, and Yahoo email has something similar). Other mail systems (e.g. GMail) allow you to add a + after the left part of your email address and they ignore that part, so if your address was, say, sunil@gmail.com, you could use sunil+abc@gmail.com or sunil+dodgysite@gmail.com and thus "mark" your registration for particular sites. You could then filter out emails sent to such addresses if they turn out to have turned "spammy".

    Most mail services have built-in antispam systems. Some (e.g. Google, Outlook and Yahoo) are very effective, others less so. The better systems learn from experience (see "Bayesian filtering" below) so it's important to classify messages as spam or not spam when the system gets it wrong.

    Many email clients have spam filtering features, but the most effective system by far is called Baysian filtering ("modified Bayesian filtering" is even better). Thunderbird has such filtering built in and there's also a free plugin called SpamBayes (spambayes.sourceforge.net) which can be used with many other email clients.
    Baysian filtering works by studying corpora of examples, i.e. a group of good emails ("ham") vs a group of bad emails ("spam"). It builds up a list of "words" (which includes any word-like items, like IP addresses and tokens in email headers) and associates them with spam or ham. As new email comes in, it evaluates the words in the incoming message and decides whether the new message is ham or spam. If it gets it wrong, the user corrects it and the lists are updated accordingly, so the system continuously learns from experience. Bayesian filtering learns remarkably quickly and importantly, it it learns over time what YOU consider to be ham or spam, and it keeps itself up to date.

    • Sunil
      August 22, 2014 at 5:45 pm

      Kindly note that "email" is last word in query but a mandatory criteria , not to be edited out of main query! Its okay , general spam combating , is also important to know. Thank you very much

  3. Dr.sunil V
    August 18, 2014 at 4:54 pm

    hi.Query is specifically for email spam but was edited out