Please be aware that these are only screenshots and nothing will happen to your computer. They are not clickable. The following is based on using Internet Explorer and concerns a feature called "Install on demand". There are instructions at the end of the post for disabling this feature
So you click on a link for an anti-spyware program or maybe its a popup or a link in your email and you are taken to a website like this:

If you don't have Install on demand disabled and you use Internet Explorer you are already the unwitting recipient of the following download. It has been downloaded and installed on your computer. You are infected with malware now. This is known as a "Drive By Download".

If you do have Install on demand disabled you receive the above security warning and you would think that you are ok. You click No. You try to navigate away from the site, but wait, what this?

No, no, no, You don't want to do this. You click cancel. Now you get this:

Now what are you going to do? I don't believe that if you clicked Ok on that box that you would have the option of Run or Open, which implies a Cancel option too. I think the download may start right away.
Its important not to panic or to get frustrated and click Ok just to make the boxes go away. Personally, I chickened out at this point. If you were using a ZoneAlarm Firewall or any other type that has an Internet Lock this would be the ideal time to use it. In order to get out of this you need to close the browser using the Task Manager/Close Programs feature accessed by using Ctrl+Alt+Delete and closing the page. The second time I went to this site when I forced the window to close I got a blue screen.
If I get brave I'll go back and click Ok on that last one.
In Firefox, you can disable the automatic install feature this way:
"tools tab", under "tools, options, web features", the
default setting is "Allow websites to install software". Uncheck that.
Thanks to our jgweed for that info.
In Internet Explorer go to Tools>Internet Options>Advanced and take the check mark from Enable Install On Demand (Internet Explorer) and Enable Install On Demand (Other). The consequence of this will be that you will begin to see Security Warnings when something tries to install on your computer. Unless it is something you want to install (which happens rarely) always say no.
Many thanks to Pandy for all her hard work on the screenshots in this post and her timely advice.


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