When I close the game it doesn't closing

If you are seeing an error like this: "Failed to start game (app already running)" when trying to launch Oxygen Not Included, it means that the Steam client may be failing to launch the game properly. Check out Steam's troubleshooting guide for this issue: https://support.steampowered.com/kb_article.php?ref=9764-IJVM-3291

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If you are seeing an error like this: "Failed to start game (app already running)" when trying to launch Oxygen Not Included, it means that the Steam client may be failing to launch the game properly. Check out Steam's troubleshooting guide for this issue: https://support.steampowered.com/kb_article.php?ref=9764-IJVM-3291

Thanks, but nothing didn't help.