My computer is infected with smitfraud.c spyware, it was detected by spybot search and destroy, but this malware keeps coming back. Anyone know best way (or tool) to remove this nasty malware?

My computer is infected with smitfraud.c spyware, it was detected by spybot search and destroy, but this malware keeps coming back. Anyone know best way (or tool) to remove this nasty malware?