Check that the saved game folder and the files in it have not been set to read-only (select the files/folders in Explorer, right click, and select Properties).
Are all saves causing this crash, or just some? Check the number of files in the save folder, compared to a working save near the same point (the game adds more files to the save after the first time you visit new loacations, like Verdistis and the Dark Forest).
Have you installed the latest
patch, or at least the version under which the games were saved?