As of the v1.0.7g game patch, WolfQuest:AE includes cloud syncing for user files. This serves as a backup if anything goes wrong with the files on your computer, which we hope will help with the issues described below.
We receive occasional bug reports about corrupted game saves or even gone missing, deleted from the computer.
When a save is corrupted, it cannot load the game simulation properly, so it freezes on an overview of the game map, and nothing the player can do will snap the game out of that state.
When the game data has been deleted, there's no way to restore it if you don't have a backup (which is always a good policy).
There is no way for the game itself to delete or corrupt a save file, but somehow, this does happen to a small percentage of players. Most likely, some other program on your computer, anti-virus or anti-malware, mistakenly decided that the game is malicious software and deleted or altered the files that the game created on the computer. If you have any such software, adding the game to its whitelist should prevent such interference. We've never seen this happen on our computers, so this is just a hypothesis -- but there's no way the game itself could mass-delete those files.
A recent report about this showed that the player's Documents were inside Microsoft's OneDrive. Possibly, certain settings of OneDrive can interfere with the game files. OneDrive does have a way to restore older versions of the files, so if you get a corrupted save, that might be worth trying. Read more here.
Also, here's a discussion about corrupted files from OneDrive-sounds like other people have problems with corrupted files due to OneDrive syncing, and this might have some tips.