exported to unity as an fbx file but it doesn't have any texture. how would I fix that problem.

Does fbx export need UV mapped textures?

i do not know but i unwrap my object to apply texture to it before i export

To my knowledge Unity will not import all materials and textures with the object from Blender. What you will have to do is go back in Blender and UV unwrap your object, EXPORT YOUR UV LAYOUT to whatever texture program you are using (gimp, photoshop) apply your textures there, and then import that as a seperate asset. As far as materials, you can create custom materials in unity itself and apply them to your object as you need to. Search the Unity forums for more answers. Its a pain in the ass process but thats the way I normally do it. Thats a sure fire way to get it done.
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