I haven't played skyrim in awhile and decided to get back into it. I am trying to make some potions but for some reason the game isn't allowing me to use hagraven claw for any potion. I have ate some, dropped some and bought new ones. My alchemy is 100. Would any one happen to know why the game isn't letting me? Thanks for reading.

it's most likely it's a game bug, skyrim still has some.

you might try reloading your saved game and see if that helps.

Are you certain you are browsing the menu correctly at the Alchemy table?

It should be listed in the ingredients.

EDIT :

Ha! For some reason I completely missed that in the OP. I think it's obvious that you know how to use the ingredients.

Maybe it got tagged as a quest item? Do you have a quest relating to Elynea Mothren asking you to find her one? This seems kinda doubtful because you said you could eat them and drop them, but who knows really.

Here's a link to that quest. http://www.uesp.net/wiki/Dragonborn:Hunting_and_Gathering