So, whenever I try to click on the wow.exe, it starts perfoming data files checks and if I let it complete, it patches my game to WoD. My client is the MoP one.

How do I fix this issue? :/ This happened before, and when I saw that the client got updated to WoD I had to re download the whole game again.

I think this starts to happen when I open my battle.net launcher to play Hearthstone.