MTCS Parasite FAQ

What are parasites?

‘Parasite' is a shorthand term for “unsolicited commercial software” — that is, a program that gets installed on your computer which you never asked for, and which does something you probably don't want it to, for someone else's profit.

The parasite problem has grown enormously recently, and many millions of computers are affected. Unsolicited commercial software can typically:

All the parasites I currently know about are only compatible with Windows, and some only affect the Internet Explorer browser. The script on this site — when it is run in IE for Windows — can detect many of them. But not all, for tedious technical reasons.

Where do they come from?

There are three major ways unsolicited commercial software can make its way on to your machine:

An alternative solution for the last two problems is just to use a different web browser for everyday browsing, and Internet Explorer only for sites you trust that stubbornly refuse to work with other browsers.

Why doesn't my anti-virus software detect this?

Technically, most unsolicited commercial software isn't viral: it doesn't spread from computer to computer, it just installs and runs on one system.

That doesn't mean it's not harmful, but anti-virus software does not attempt to detect all software that could be harmful. Whether it should is a tricky argument that ends up a question of where you draw the line.

Actually some anti-virus programs do detect some of the parasites outlined on these pages, but not nearly all, and not all versions of them. Parasites that install using IE security holes are more likely to be targeted by the anti-virus software vendors, but the selection of targets seems for the most part to be pretty arbitrary.

For this reason there are now a number of anti-parasite packages around that work as a complement to anti-virus software.


General information

Free anti-parasite software

Commercial anti-parasite software

Questionable anti-parasite software

Since the issue of adware and spyware has become better known, many companies have been jumping on the bandwagon and offering anti-parasite software. Not all are as trustworthy as one would hope, for a company offering to take care of your computer's security.

Other security services