The Complete Edition of GTA IV unified the base game and its DLCs, but it also stripped away crucial features due to expired music licenses and replaced the old, mod-friendly architecture with restrictive launchers.

Open your Steam library, right-click on , hover over Manage , and select Browse local files . Keep this folder window open. Step 2: Run the Downgrader Tool Launch the downloaded GTA IV Downgrader executable.

Handle the launcher / social club / DRM