Select the [...] next to the Play button > Manage > Files tab > Verify and Repair . 3. Manually Copy Missing Zone Files (Plutonium Users)

Corrupted config files can sometimes confuse the "zone" locator. Go to the players folder in your directory.

Before we dive into fixes, it helps to understand why this happens. The ".ff" (FastFile) format is proprietary to the Call of Duty engine. These files contain all the game data: textures, sounds, maps, and scripts. The "Zone" refers to a section of memory where these files are loaded.