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Blocking is an ineffective way to prevent unwanted emails. It's better to learn spam filtering.

I have Vista Home Premium and an Acer M1640 and Hotmail. Sky is my ISP. When I get emails in the junk file, I click on "sweep," "block from," and then "block all," but many of them keep coming back, showing the date that they first appeared. How can I make sure that they are blocked so that they don't come back?

In this excerpt from Answercast #29, I look at attempts to block spam... that just don't work so well.

How to keep blocked emails blocked

Unfortunately, I don't think you can.

Blocking is a clumsy attempt at preventing spam at best. Not your clumsiness, but the system's clumsiness. It just doesn't work well at all... no matter what system you're using. There's a couple of reasons for that, that I'll get into.

Blocking limits

The other problem is that with Hotmail specifically (and apparently with other systems as well), there is a limit as to how many email addresses you can block.

I think it's something like 500 for Hotmail, which, if you're blocking regularly and frequently, you can reach in no time at all. At that point, you don't get any error messages; it just stops blocking new things you ask it to block.

The problem with blocking

The problem with blocking is very simple: when you block something, you're blocking a specific email address. So, if you were to block email from me, it would just be looking at my email address. Anything that comes from that email address would be dumped into your junk mail folder immediately.

  • The issue is that spammers know this... so they routinely change the "from" address.

You'll rarely see the same email from the same address, particularly when it is spam. So, as a result, you're free to block whatever you want to block: but that spam is going to show up again from a different email address which is not blocked. You can block that one and then it will come from another one that's not blocked.

As you can see, this quickly turns into a point where you're spending more time blocking than you are actually reading your email.

So, my recommendation in general is this:

  • When you get spam that's not in your Spam folder, mark it as spam so that the system learns what is and is not spam.

Check your junk mail folder every once in awhile to make sure that it's not occasionally marking as spam something that it should not mark as spam. Make sure that then gets marked as "Not Spam"... so that it will continue to show up in your inbox.

And that's it.

Various systems for blocking

Blocked email will probably show up in your junk mail folder; because that's what blocking may automatically do.

It's hard to know exactly what "blocking" means. The fact that something shows up in your junk folder may or may not mean that it's been blocked. Blocking may simply mean, "Always send this to junk."

So, don't spend a lot of time trying to block and unblock; I really think it's not worth the effort at all.

If you're going to spend time trying to train the system as to what is and is not spam, use the "Spam" and "Not Spam" buttons; or the "Junk" and "Not Junk" buttons (in their appropriate context) to let the system know what emails you think are spam. It will learn from more than just who it's from; it will learn from the content of the email what is and isn't spam.

Those will automatically get sent to the junk mail folder where you don't have to look at them unless you specifically want to.

Next from Answercast 29 – Does https hide email addresses in Hotmail?

Article C5514 - June 25, 2012 « »

Leo Leo A. Notenboom has been playing with computers since he was required to take a programming class in 1976. An 18 year career as a programmer at Microsoft soon followed. After "retiring" in 2001, Leo started Ask Leo! in 2003 as a place for answers to common computer and technical questions. More about Leo.

Not what you needed?

Rod Minnich
June 26, 2012 3:43 PM

I use Hotmail and here's what I did to keep most junk/spam out of my inbox. I set my junk e-mail filter to exclusive which allows only e-mails from someone in my contact list or on my safe sender's list to go to my inbox. All other e-mails go to my junk folder. I check my junk folder periodically, in case a "good" e-mail was sent there incorrectly. All the rest I just delete. Just an idea for others to try who are tired of wading through junk/spam e-mails.

June 26, 2012 5:19 PM

Seems like a good suggestion, Rod. I've pretty much abandoned my Hotmail account because it seems to have a serious "learning" disability when it comes to recognizing spam (no matter how many times I report the same type stuff).

June 27, 2012 8:04 AM

Well said.........
There is no end for that sort of thing.
As LEO said, take it easy and relax.
Any mail (hotmail or else) cannot afford protecting you from 10's of thousands of undesired mails and billions of mails for others !!
It is sad, waste of time and money for the whole world.

June 28, 2012 8:39 AM

Depending on the program used (and in general i'm not talking about web-based e-mail providers), some let you block at the sub-domain and domain levels. But blocking is only likely to have an effect on the 'innocent' e-mailers, as the criminals already know a way around it; spammers can get the 'To:' field to display whatever they like these days.

July 14, 2012 9:49 AM

''some let you block at the sub-domain and domain levels. But blocking is only likely to have an effect on the 'innocent' e-mailers''

yes even Hotmail have this service but it is not limitless..
even can block any word from the address name, but still sometimes as you said it has an effect on the mailers..

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