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Does spam blocking prevent spam from reaching my machine?

Question: I just discovered “blocking” to keep spam from coming in my mail box. I’d been choosing words to make the spam go to the deleted messages folder but seemed I couldn’t keep up with them. I’d also tried to write back and “unsubscribe” but then I’d get a message that said it bounced. So I found blocking and am giving that a try. Now, does this keep the message from ever getting into my computer or does it accept it and then delete it?

Welcome to the world of spam – and the never-ending battle against it.

Choosing words and blocking based on that is one approach, but as you noted it’s tough to keep up.

In fact, it’s darned near impossible.

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I do want to start with one point: Never EVER click on an “unsubscribe” link in email that you didn’t actually sign up for. It tells spammers that they found a real, live, email address, and it’ll result in more spam, not less. That being said if the email is legitimate (perhaps follow on mail from an on-line store you shopped at, or a newsletter or mailing list you joined), then yes, please do use the unsub link. I know it’s hard to keep straight sometimes.

And while we’re on the subject, please, PLEASE, only use any “report this as spam” button for actual spam – it’s not the way to unsubscribe from something you signed up for and actually harms legitimate businesses and spam fighting efforts.

Back to word-based blocking.

Spammers in particular will intentionally misspell words to bypass blocks. If you’ve ever seen spam full of misspellings, or odd character selections, you’re probably seeing exactly that. It’s impossible to predict all the possible combinations of words and characters that spammers might use to get a concept across.

That makes it difficult, if not impossible, to block spam by just choosing words.

On top of that of course you might pick a word to block that someone uses in some legitimate way, and you’ll miss their mail. This happens to me on occasion.

Whether or not blocking prevents mail from reaching your machine depends on the blocking service you’re using; there are several approaches. If it’s done on a website provided by your ISP, for example, then yes, that would most likely prevent the mail from even being downloaded. On the other hand, if it’s a setting in your mail program, then that’s something that happens after the mail gets downloaded.

So what can you do? My earlier article How do I get rid of all this SPAM?!?! discusses some of the options.

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2 comments on “Does spam blocking prevent spam from reaching my machine?”

  1. Yes, for those that have the ability to control their own mail server, or for those ISP’s that have the option, spamassassin is great. I have it myself, as do most of my clients. It’s not perfect, but it’s very good.

  2. Oh well, I will mention this program also here (beside the one in/under the “Why shouldn’t I use the “Report Spam” or “Junk” button?”: article), since it’s a related topic and I have all the text already written …

    I recently discovered an only 81 KB in-size FREE anti-spam program from Keir software called K9; see here: In short, K9 is an anti-spam application that “sits” between the remote e-mail servers and a local e-mail client (for instance Outlook, Thunderbird etc.); so it’s not the type that only checks the servers for spam (however, it can also do that), but “ignores” the e-mail client. And well, it’s also available in the “non-setup” form (the form of programs I prefer), i.e. a .zip archive, and no installation procedure required. Yeah, I know that this might sound strange, but that was the main reason for trying it in the first place.

    best regards,
    Ivan Tadej, Slovenija, Europe


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