Helping people with computers... one answer at a time.

Advertising networks are quite sophisticated and use cookies to track your movements through the internet. But don't worry. It's an attempt to help you find the products you are looking for, not spyware!

After visiting major online computer and electronics retailers' websites, I find that they have tracked items I looked at, combined with my computer's browser settings or web address and then displayed these items as pop-up ads in my other browser pages. I believe something from the computer store website has inserted spyware into my IE9 browser settings and I refuse to trust any spyware. If I increase the security settings, many sites I need to visit no longer function. I have pop-up blocking enabled and expensive anti-virus working, but this is circumvented. I can individually block the sites, but how or what can remove their new spyware from my computer?

In this excerpt from Answercast #42, I look at that scary feeling when you visit one site and then encounter ads for those same products on another. Don't worry – it's not spyware.

Online advertising

My friend, you are not seeing spyware. What you are seeing is termed in the industry "remarketing."

What it means is that you have visited a site that uses an advertising service from one of several companies that do that.

Google online advertising

I will use Google's AdSense, or AdWords, as the example here. What it boils down to is:

  • You visit a site;

  • And yes, they leave a cookie on your site

  • It may say, I visited site X.

  • Now, when you go to other websites that happen to use the same advertising partner, they may elect to show you ads related to the sites you've been to before.

As a concrete example, I will often visit the website of the hosting company that I use,

I do that because that's how I manage my servers. It's interesting because then, gosh, it seems like for days, on completely unrelated sites, I will end up seeing advertisements for LiquidWeb.

Advertising network tracking

All it really means is the advertising network has noticed that this computer, not you as a person, but that computer happens to have visited a site that is an advertising partner. Then they assume from that, that "OK, maybe this computer, the person behind this computer, has an interest in whatever that advertising partner has to offer."

  • So, they simply run ads relating to that advertising partner when you visit other sites.

It's not spyware

That's all it is. It is not spyware on your machine.

There's nothing you can do about it without going and getting an ad blocking solution – which of course, being an advertising supported site, I cannot support using ad blocking technology.

But that's about it.

  • In my opinion, it is totally benign.

I know that it freaks some people out, and kind-of understandably so. But ultimately, there's really nothing underhanded going on here. There's nothing nefarious going on here.

To use your terminology:

  • It is most definitely not spyware.

Article C5670 - August 8, 2012 « »

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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?

Pat Kerr
August 10, 2012 8:32 AM

Interesting article, but what should be noted is your privacy is violated. A friend of mine, did a search for a product for his personal hygiene, now every page he brings up has ads for this everywhere. Why would this matter? Because he has friends and clients that view his computer screen while he is working with them on projects, and now they see what he was looking for. Not very private anymore, huh?

August 10, 2012 11:07 AM

That would be a case where clearing cookies would be a really good idea! It's a pain because any memorized passwords and sign-ins also go away, but it should make the advertisements forget where he was browsing!

August 10, 2012 3:09 PM

Sometimes an installed toolbar can be the culprit. I was getting ads related to things I searched for in the past, and it didn't matter how often I cleared out my cookies. Once I unistalled the toolbar (Google Toolbar, to be exact), the ads immediately stopped coming.

August 10, 2012 3:32 PM

Use CCleaner to clear cookies but add those cookies for passwords and sign-ins to the "Cookies to keep" list. That way you can eliminate the advertising cookies.

August 11, 2012 1:45 AM

In your answer you stated that, "...being an advertising supported site, I cannot support using ad blocking technology."
It's obvious, to me anyway, that's a personal opinion. What's your professional opinion, aside from the fact you run a website?

Personal and professional is the same: ads are one thing that keeps free websites free. If everyone used adblockers then I and a LOT of other sites people rely on would be unable to continue to exist. It's pretty simple. If ads are THAT annoying then vote with your feet and don't return to the site.

Mark J
August 11, 2012 8:29 AM

That is a professional opinion. If everyone using Ask Leo! used an ad blocker, he would no longer be professional but amateur as he would no longer be able to make any money from the site. These ads are what makes sites like these possible, unless of course a lot of people prefer to buy Leo a latte :-)

August 11, 2012 10:27 AM

Many thanks for your recent news letter, concerning setting up a wireless network, using
an access point and adaptor, I've now bought these, and linked up my internet enabled tv!
Very interesting, as before I thought that I would
have to buy lots of ethernet cable to link it up,
So its thanks again Leo.

August 12, 2012 6:00 PM

This is more complex than a cookie. I saw more info than website location being recorded by computer retailers. The types of items I viewed were also recorded and stored somewhere and shown again. Someone please tell the whole story. What personal information is being recorded and where it is stored?

August 14, 2012 4:38 AM

While I understand the technique in this process, it's rationale seems a major goof by advertisers. I surf and see ads for Kaspersky which I run - why - why not a competitor. I subscribe to and use frequently Consumer Reports and yet I see ads for it all the time. It amuses me but seems kind of useless to advertisers which is also amusing as they are always trying to get one to buy something.

Eric Brightwell
August 19, 2012 2:22 AM

We all respect your opinion Leo, otherwise we would not visit your site so often. However, if ads were text only, then ad blockers would not be needed. But these ads with large graphics files are actually stealing part of your monthly bandwidth when they download themselves. On this basis I cannot see why ad blockers are any different to putting locks on your door to try and prevent burglars coming in.

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