
What your co-worker is referring to is the HOSTS file which is located in this folder C:/Windows/system32/drivers/ect. Some virii will hijack your HOSTS file and the effect of this is that when you go online you will get redirected (without your knowledge or permission of course) to some other web site at which point you will have a ton of bad stuff downloaded on to your system, and Hey Presto! you are now infected.
To learn more about the HOSTS file click the link here to the Forum tutorial:
http://www.briteccomputers.co.uk/forum/tutorials-and-how-to/blocking-websites-using-the-windows-hosts-file/msg1654/#msg1654Cheers,HTH,
ticker