I have the GOTY version 1.31. Game worked fine for a long time, but I last played it in October. I just purchased a new SSD and I used a program called Steam Mover to migrate my games from my main SSD to the new shiny one. I forgot that my Witcher 3 game was from GOG, but does it really matter? All steam mover does is migrate the files.

I returned to Witcher 3 recently and when I go to load a game I get an error stating that all my DLC is missing. However, if I go to the DLC folder, everything is there.

How can I fix this? Do I have to reinstall?