DX11 assimp - sizeInBytes layout error

i have some problems with some obj files, using dx11 assimp nodes.
I’ve buyed online, and i have it multiformat. i’ve tried the original obj first, then also tried to convert them in my 3d software (lightwave), but in both case, only some of the .obj works. the others gives an error (coming out from the phong shader), that says:

“Argomento specificato non compreso nell’intervallo.
Nome parametro: sizeInBytes”

so, in the meantime i’ll try other formats and reconversion, and i’m sure i can resolve some way by converting and “altering” the original 3d model, but do someone knows if there’s a way to see that files, or why they are not readed correctly?

just a guess: have you tried looking at layout differences between obj files that work and others that don’t? it might be an additional set of uvs or similar.

resolved, was a problem about uvmaps, exactly