Armature modifier not working after Apply

Hello everyone,

So I made this simple model in blender, made up of four meshes. I then created vertex groups for these meshes, added bones and named everything correctly. After that I added some Armature Modifiers to the meshes, and set in those properties(object,vertex group). After this, I tried to move one of the boes in POSE mode and everything work like it should. So I clicked APPLY on the modifiers, and after that, bones stop to deform the mesh as I move them. Whats wrong? How can I fix this?

Best regards!

Whats wrong? How can I fix this?
You don’t apply the Armature modifier, that’s what allows the bones to modify your mesh
http://wiki.blender.org/index.php/Doc:2.6/Manual/Modifiers/Deform/Armature

But, if I dont apply the armature modifiers and try to export this model to .fbx and import it into Micorosft XNA. It throws me an error saying: “Error normalizing vertex bone weights. BoneWeightCollection does not contain any weighting values.”.

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