Verifying your game files
If you're having issues with one of your games on Steam, whether it's glitching, lagging or crashing, it may be caused by corrupted or missing game files.
When verifying your game files, your Steam client establishes if this is the case and replaces any that are missing.
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How do I verify my game files?
To check your game installation and make sure that there are no corrupted or missing files causing the problem: