The warning message ('Invalid Game Data') will continue to be displayed until the Dark Souls III server team has determined whether or not a violation of the End User License Agreement (EULA) occurred. This message is intended to inform end users that some external file, modification of game save data, exploit or cheat/hack, or alterations to the game have been detected by the Dark Souls III server team and that the end users' account/profile has been flagged for further investigation. 'Invalid Game Data' warning message on Main Menu after starting up Dark Souls III

You can create backups of your data, but if you encounter an 'Invalid Game Data' message, see below.

You can do this by going to control panel and clicking on Appearance and Personalization or File Explorer Options in Windows 10, click on the 'View' tab and check the box for 'Show hidden files, folders and drives' then press ok.

It's possible that the folders are hidden so unhide them in your folder settings.Saves for Dark Souls 3 are located in your /C>Users>'username'>AppData>Roaming>DarkSoulsIII.

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