One rather effective way of keeping your computer clean and uninfected is to block access to known bad sites via the hosts file.
Since this is very well described on MVPS.org I won’t repeat it here.
With a little ingenuity, sysadmins can even automate the collecting of the updated file daily and distribute it to all client computers via the login script.
Here is a warning though: If you use a large hosts file on your servers, don’t use DCPromo without temporarily renaming the file.
DCPromo will CRASH and reboot your server 30 seconds later if a large hosts file exists! I found this out the hard way some time ago. It took a $295 phone call to Microsoft Tech Support where I had to try to understand India’s version of English for about 10 hours over a 5 day period.
I had to download numerous utilities, zip several dump files and send to Microsoft, and basically ruin a week of my time. Finally, I got the problem escalated to a supervisor (still from India) and she figured it out in about 20 minutes; seemingly without the help of all the work that had been done beforehand.
Running a hosts file that large can be a benefit for security purposes, but be forewarned that DCPromo can’t handle it.
