Well normally it should work. Downloaded Feral Heart again (due to some problems) Had the same error. Deleted all the Feral heart files - re downloaded it - worked.
Just to double sure, try searching "Feral Heart" either in the Start Menu or in Local Disk (C:)
If you spot any, delete them. Or maybe go to your recycle bin and search for Feral heart then delete the folders/files...
I certainty have no clue, but I wish you luck.