Are there three black and white wires in light box?
If so then you have what is called a switch loop. This is where you have a power in and out of a light, thats two wires, and a wire that goes to a switch. Generally a white wire in the light box is tied to the two black powers, and goes to switch, and comes back on the black wire to be hooked to light. The other two whites are neutrals and hook together with white from light fixt. If any of this makes sense you could pull down light and have a look. Then if its greek you could tell us what you see in there then we could surely help ya out. Good luck.....
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