Missing files that aren't missing

Hi everyone!
I'm a newbie here, but I've been playing this game for quite a while. Anyway, I just downloaded the "Program" and the "Cumulative Folder", and put them in "C:\Program Files (x86)\Magic\Program" according to the instructions I found here. The game starts correctly, and even the duels are working.
The problem is with the Deck Builder. When I click it, the game crashes and shows the message "Couldn't find Cards.dat, DBInfo.dat or Rarity.dat", but these files are in the folder.
I've tried changing the folder, the folder name, the compatibility mode, but nothing seems to work.
Any ideas?
I'm a newbie here, but I've been playing this game for quite a while. Anyway, I just downloaded the "Program" and the "Cumulative Folder", and put them in "C:\Program Files (x86)\Magic\Program" according to the instructions I found here. The game starts correctly, and even the duels are working.
The problem is with the Deck Builder. When I click it, the game crashes and shows the message "Couldn't find Cards.dat, DBInfo.dat or Rarity.dat", but these files are in the folder.
I've tried changing the folder, the folder name, the compatibility mode, but nothing seems to work.
Any ideas?