I think I already know the answer to this one but i suppose it never hurts to submit ideas. "The necromancer calls forth his powerful magic to remove the enchants of magical items. If the necromancer fails his attempt to disenchant, the item loses its ability to accept further enchants from the powerful magi."

Sorry bub, this has been shot down in the past for the reason that we don't want players having the opportunity to try and try and try to get a perfect enchant. Addiotnally the outcome you propse on failure is the same as the outcome currently in place after any enchant (as in you can't re-enchant).