Unless you are performing digital forensics or need this specific version for a legacy Windows XP/7 machine, there is little reason to use it today.
: Released around December 2009, this version introduced improved compression speeds for multi-core processors. WinRAR.v3.91.x64.Incl.Keyfilemaker-CORE--tracker
WinRAR is perhaps the only software in the world where the "Incl. Keyfilemaker" tag was almost a formality. The company behind it, , famously allowed the trial to continue indefinitely. This led to a decade-long internet meme about "buying a WinRAR license" being the ultimate sign of digital philanthropy. Unless you are performing digital forensics or need