Browser hijacking is one of the web's constant dangers. Whether it arrives in the form of a flood of obscene pop-up windows assaulting you after a mistyped URL, or malicious code taking over your browser completely, chances are good that every Internet user will be subjected to this practice in some form.

Fortunately, avoiding a browser hijacking is not impossible if you stay aware, and take a few simple precautions. Take the metaphor of locking your car doors while you are out for a drive as an example. If your browser keeps redirecting you to www.somerandomsite.com and you are here looking for ways to cure what ails you, we'll cover that too.

To sum it up, this PCstats Beginners Guide will show you how to avoid and defeat these annoying and potentially embarrassing attacks on your computer, starting with seven preventative measures;

1. Use common sense
2. Use and update an anti-virus program regularly
3. Use antivirus 'auto protection'
4. Keep an anti-hijack 'toolkit' for emergencies
5. Change your Internet Explorer security settings
6. Try an alternate browser

What's a browser Hijacker?

This term covers a range of malicious software. The most generally accepted description for browser hijacking software is external code that changes your Internet Explorer settings. Generally your home page will be changed and new favourites will be added that point to sites of dubious content. In most cases, the hijacker will have made registry changes to your system, causing the home page to revert back to the unwanted destination even if you change it manually.

A browser Hijacker may also disallow access to certain web pages, for example the site of an anti-spyware software manufacturer. These programs have also been known to disable Antivirus and anti-spyware software.

Most browser hijackers take advantage of Internet Explorer's ability to run ActiveX scripts straight from a web page. Generally, these programs will request permission to install themselves via a popup that loads when you visit a certain site. If you accidentally give them permission to install, IE will execute the program on your computer, changing your settings. Others may use security holes within Internet Explorer to install themselves automatically without any user interaction at all. Worse, these can be launched from popup ad windows which the user has not even intended to view.

As well as making changes to your home page and other Internet Explorer settings, a hijacker may also make entries to the HOSTS file on your system. This special file directly maps DNS addresses (web URLs) to IP addresses, so every time you typed 'www.pcstats.com' (as an example) you might be redirected to the IP address of a sponsored search or porn site instead.

Some browser hijackers may also install themselves onto your computer system as legitimate programs, leaving an entry in the 'add-remove programs' list in the control panel. There are many faces of broswer hijacking, and to combat the situation, you have to be aware of all the tricks and loopholes that make this scourge possible. Browser hijacking isn't necessarily a virus, and isn't necessarily adware, so stopping it isn't necessarily best left to software monitoring programs either.