I have a problem import a character

I made a character throught 3dsmax2015

and I rigged it that by maya2014(I didn’t know when I rigged, have a fomular skeletal mesh in UE4 for maya)

so I rigged it by maya2014 like by animation character rigged.

when I import skeletal mesh, always pop warnings up.
duplicated bone found. each bone name must have a unique name. Error Multiple roots found.

what I miss?