Search for "Ice AI Traffic V6.00 FSX download" on reputable flight sim forums (AVSIM, FlightSim.com, or Rikoooo). Always scan the zip file for viruses—community mods are usually safe, but caution is wise.
If you managed to grab a copy of this legacy installer, keep these performance tips in mind: Traffic Density : Set your airline traffic density to around Ice Ai Traffic V6.00 Fsx