Plays nicely with others: HitmanPro 3 doesn't need to be installed to work but even when we opted for installation, there were no issues with our current antivirus program. HitmanPro 3 (64-bit) doesn't claim to be the primary solution for your PC security needs, but it does add another layer of malware protection and what the publishers describe as a 'second opinion' to see if your computer is infected and help you remove any unwanted files.