I've already created the mesh and armature. I weight painted the mesh and was able to make two, perfectly fine, animations (walking and running). However the next time i opened this file, the armature and animation was still there, however the mesh wasn't moving with the armature. So when i would play an animation all you could see are the bones moving while the mesh stays still. This is the second time that this is happening and i was hoping that there may be another way to fix this rather then re-doing all the bones and weights.
UPDATE: ok so i was able to find the .fbx (because i also exported it as an .fbx for unity) folder and imported into Blender. Anyway it is now working (except the inverse kinematics disappeared) anyway is there anyway to fix this problem so it doesn't happen again?