That problem goes through several things:
1- You did not import the cff file in the same iff file from where you got it.
2 - it could be that you put the 3d model in another iff file that is not the same from which you took the 3d model.
3- I mainly gave that same error, when I added the long hair, from another 3d model to the cyberface model of Hanley Ramirez, altering the vertex numbers and as a result a deformed model. in conclusion you added or removed something to that model and that's why you have that problem.