Spanish Files corrupted

I attempted to access the Spanish language course, and all of the pdf files are corrupted or bad. The error message from Adobe Acrobat simply says "there is a problem with the file. "
I attempted to view the files both online and as a saved file from my harddrive.
I was able to access the German language files, as well as the japanese
I attempted to view the files both online and as a saved file from my harddrive.
I was able to access the German language files, as well as the japanese