HijackThis is an advanced malware removal tool that should only really be used if your browser or computer is still having problems after running other less advanced anti-malware. HijackThis requires advanced knowledge about operating systems and if you delete items that it shows, without knowing what they are, it can lead to other problems such as your Internet no longer working or problems with running the OS itself. You should attempt to clean malware with all other methods before using HijackThis.