Go to http://majorgeeks.com/BHODemon_d3550.html
Grab the BHODemon software.

The ISTsvc is a toolbar that uses open IE Browser Helper Objects to install itself. This is what changes your homepage and also redirects your searches to sites other than what you choose.

You should stop using IE, or lock it down to Paranoid security settings, this is cumbersome as you will be prompted to click on every little thing to Allow or Disallow it for every site you visit.

Another solution once you are rid of this pest, the most common is to stop using IE, there are many other freely avaible web browser that are just as good and don't interact in ways not intended.

IE is an excellent program, it is by no means solely at fault. These programs take advantage of other bits of software to run as the service running the browser to hide themselves from the users view. Most likely ActiveX scripting, VB scripting, malicious Java, take your pick.

Another option if you insist on using IE is to modify your HOSTS file to block or allow certain sites. This will directly take the security away from Windows and put it in your hands. There are a few ready made hosts files, with well , known adware/spware sites already on the list to block. You can find one here. http://pgl.yoyo.org/adservers/


I also suggest you take some time to study up on how this happens. By doing this you will arm yourself to defend against it, and you will cease to be a victim of it.

Best of luck to you.