My first experience with a spyware BHO based infection was several months ago. I had gone through all of the usual steps with the client's machine to clean it. Ad-Aware was run, Spybot: Search and Destroy was as well. Nothing looked suspicious in the system's startup. All appeared well, but it wasn't.
After extensive testing and no further symptoms I returned the computer to my client's home. I hooked it back up, and dialed the internet. Everything so far was progressing smoothly. But, as SOON as I loaded Internet Explorer: BAM the same pop-up advertisements and other annoying things started happening again. With much embarrassment I had to take the computer back to my office and try again.
It was all Internet Explorers fault. Microsoft Internet Explorer comes with a feature that is designed to add third-party functionality to their browser. It's actually a very good idea. Unfortunately, it now gets taken advantage of.
The producers of spyware know that many people now have spyware removers installed on their computers. They also know that quite a few people have the ability to check what is in their start-up. Because of this, BHO's are crafted so that the spyware lies dormant until Internet Explorer is opened. Then it can start its dirty work.
The best program to remove an errant Browser Help Object is HijackThis. This program was originally designed to remove homepage hijackers and gradually morphed into an all-around removal tool for everything. If there's any one tool that I couldn't part with it's HJT.
To start, download HijackThis 1991. http://www.spywareinfo.com/~merijn
Once you've got it, open it. Click the button that says "Do a system scan only". Following that, scroll down to the items labeled 02 - BHO. Remove anything here that looks suspicious. Internet Explorer does not require any BHO's to run. Just keep an eye on the path that it loads from, and the name of the file. A legitimate one will be fairly easy to spot, as it'll have a legit title and OK looking path.
If the filename looks like it was randomly made, like ASGSRT32.DLL or whatnot then there's a good 90% chance that it's bad. Even if you do remove one that's good, you can always use the restore feature of HJT to bring it back.
About the author:
Kevin Souter is a full time computer technician and operates a computer repair site, as well as a free spyware removal site. http://TweaksForGeeks.comhas articles and tutorials on all sorts of computer problems from internet issues to hardware defects, for the novice and the expert. http://EradicateSpyware.nethas been set up to teach you how to remove annoying Spyware / Adware / Malware from your computer.
