WistaAntivirus (or Wista Antivirus) is a fake spyware removal tool. WistaAntivirus was created by the same hackers that created WinDefender 2008 (WinDefender2008) and it was created to trick and scare users by generating fake error messages, fake scan reports claiming that users computer system is infected with dangerous malware, trojans or adware. WistaAntivirus wants to trick user into purchasing the "full" version of the program by showing misleading warning messages and scan results and with saying that their program will “remove” reported problems after purchasing the "full" version of WistaAntivirus. However, WistaAntivirus is NOT going to clean users computer from reported problems but might actually expose user to more security threats. Do not trust WistaAntivirus program and delete it as soon as possible!