As a final attempt, try renaming the file to a generic extension (e.g., .dat or .bin ) and open with a text editor or media player. This rarely works but may reveal plain text or common headers.
Type chkdsk C: /f /r (replace C: with the drive letter where your game is installed). Press . Unable To Open Bigfile Bigfile.000
If your bigfile.000 is part of a split archive (e.g., .001 , .002 ), and one part is missing or corrupted, you might still recover data. As a final attempt, try renaming the file