Does X-Axis Mirror work on a mesh? I applied X-Axis Mirror to a set of bones and it worked but not on the mesh, I tried to mirror the mesh using the X-Axis Mirror option but it doesn't mirror anything.
Here's the .Blend.
The mesh isn't exactly symmetrical.
This behavior is intentional. Meshes which are almost (but not quite) symmetrical wont detect vertices as mirrored.
This is needed to avoid problems with high-poly meshes where vertices may be very close.
To resolve the problem, you can use the Snap to Symmetry tool.
See: Mesh -> Snap to Symmetry.
This has options to select a distance threshold and choose which side of the axis to use.
This is because your mesh is not symmetrical.
X mirror looks for a corresponding vertex on the opposite side of the object's origin:
Grabbing the vertex at
1 will look for a vertex at
If your mesh is not symmetrical, chances are there is no vertex at
2. If there's no corresponding vertex, then X mirror can't do anything.