Drive safely, cousin.

Then, the grey box appears.

Navigate to C:\Users\[Your Username]\Documents\Rockstar Games\GTA IV\ Right-click the GTA IV folder. Go to Properties > Security . Ensure that your user account has Full Control . If it doesn't, click "Edit" and grant it. Crucially: If you use OneDrive, right-click the OneDrive icon in your system tray, go to Settings > Backup, and ensure the "Documents" folder is NOT being backed up/synced. OneDrive constantly locks files, and GTA IV throws a fit when it tries to write a save file that OneDrive is currently uploading. 2. The "Saved Games" Schism Windows has two places where games save data. GTA IV uses the "Documents" folder, but the Games for Windows Live (GFWL) remnants sometimes tried to use the "Saved Games" folder. If your "Saved Games" folder is redirected to a network drive or is corrupted, the game gets confused.

The truth is that the error message is a relic. It is a generic, catch-all error code from the mid-2000s that Rockstar implemented to cover a multitude of sins. On the Xbox 360 and PlayStation 3, this error did usually mean a corrupted memory unit or a full hard drive. But on the PC (Steam, Rockstar Launcher) and modern consoles via backwards compatibility, this message has mutated into a phantom limb. It hurts, but the limb isn't there.