You likely downloaded a Tunedata from a different region (EU vs. US). The EXE files differ. Ensure your game is updated to the official Patch 3 (latest official patch for PC). The original Tunedata is built for the disc version 1.0, but works with Patch 3.
However, as the years passed, many players realized that 2K Sports had actually struck a fine balance with the of the Tunedata.iff. When you download "mega-mods" or total conversion patches (like UBR or Med’s Roster), they often include their own Tunedata. This can lead to: Nba 2k14 Original Tunedata.iff
Use a tool like 2K Explorer or NBA 2K14 Red MC to view the raw slider values inside tunedata.iff . The original has “GameSpeed” set to 50, “Contact Shot Success” at 45, etc. You likely downloaded a Tunedata from a different