WowAce

When I try to use decursive for Devour Magic my character says "I Can't Target that" Is there a set up item I need to adjust?

what version of WoW are you playing in?

I am in Cata Classic

Can you post what the description of your devour magic says? Does it work if you use it through the standard action bar button?

I can use it thru the action button, nothing is showing on the screen when I try to use Decursive but the character says (I can't Target that" and it does not remove the debuff.

Actually the bug was that Decursive wrongly assigned Devour Magic to cure Magic debuffs on friendly units while it only works on hostile ones. This is fixed in the latest alpha I just released.

ref: https://www.wowhead.com/cata/spell=19505/devour-magic