The bow you have for your hunter is equip lvl 85. You must use legacy scrolls that are equip lvl 85. The legacy scroll you are trying to use is max equip lvl 75. The XP lvl of the bow (or any LI for that matter) is irrelevant. The legacy scrolls you have in your bank or inventory that are for equip lvl 75 or lower are now just vendor trash. Hope this helps.
"Dwelling on the past only ensures that you will fall in the future."
I do not suffer from insanity, I enjoy every minute of it.