large white splotches

[mash]

Having a problem with a render.
I'm getting these large white splotches on an imported object.
I've seen this before and for the life of me cannot remember what the solution was.
Any ideas would be helpful.
thanks[attachimg=1]

[Dune]

Some textures probably have an alpha mask that is not set as such, or not needed but present in the texture file.