HijackThis

HijackThis is a must have tool for advanced users. TrendMicro's website says:

"HijackThis™ is a free utility which quickly scans your Windows computer to find settings that may have been changed by spyware, malware or other unwanted programs. HijackThis creates a report, or log file, with the results of the scan.

IMPORTANT: HijackThis does not determine what is good or bad. Do not make any changes to your computer settings unless you are an expert computer user. ... Not an expert? Just save the HijackThis report and let a friend with more troubleshooting experience take a look."

So HijackThis lists all installed browser add-ons, buttons, startup items, search engine settings etc. If you find something that is causing problems, you can easily remove them using the tool itself.

Here is what a typical log will look like:

Logfile of HijackThis v1.98.0
....
Running processes:
E:\WINDOWS\System32\smss.exe
E:\WINDOWS\system32\winlogon.exe
E:\WINDOWS\system32\services.exe
E:\Program Files\Internet Explorer\iexplore.exe
E:\Program Files\Microsoft Office\Office\FRONTPG.EXE
E:\Documents and Settings\Sootah\Desktop\HijackThis1980.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = http://www.google.com/ie
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://www.google.com
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.theregister.co.uk/
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://www.microsoft.com/isapi/redir.dll?prd=ie&pver=6&ar=msnhome
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - e:\program files\google\googletoolbar2.dll
O18 - Protocol: ms-help - {314111C7-A502-11D2-BBCA-00C04F8EC294} - E:\Program Files\Common Files\Microsoft Shared\Help\hxds.dll


You must be an advanced user to realise which is a virus or spyware or crapware and which is not. You may end up with a crashed system if you don't know what you are doing. Once you are very certain that a program is unwanted, go ahead and remove them with HijackThis and get rid of it.

If you do not understand fully what to do, but are having a problem with your PC which you suspect is due to a virus/spyware, you can visit so many forums that help you see what is wrong.

Download HijackThis from Merijn, Download.com.

For detailed information on how to analyse the HijackThis Logs, visit about.com's article.