I've tried to answer this question: Removing Armature and Keeping pose and apply the Armature Modifier, when suddenly the 'Modifier is disabled, skipping apply' error window appeared. How to fix it, so I may apply the modifier?
Without proper settings a modifier is "disabled" as it can't perform it's task. To enable a modifier, suitable options need to be chosen - for the armature modifier that is assigning an armature to it.
Given that the modifier is not doing anything you could also delete it without effect.