: Background applications (like overlays or system monitors) may be accessing the file simultaneously.
: Open Command Prompt as Admin and type chkdsk /f . You may need to restart your PC to allow the scan to complete. Why this happens specifically with "Bigfiles" unable to open bigfile bigfile000 exclusive
Antivirus software often "hooks" into large files to scan them for threats. If your antivirus is scanning bigfile000 exactly when the game tries to open it, the "exclusive" request will be denied. : Background applications (like overlays or system monitors)