Hi
I’m converting a .blend file to the .X format using the blender exporter
but when I try to import this .X file back to Blender it doesn’t work!
I also tried to read the exported X file with microsoft’s XNA but it couldn’t.
Does the blender exporter even work?
thanks 
I think you did something wrong; my exports and imports work nicely.
Imports from .x only give you the mesh, without any animations.
Exports to .x don’t support shape keys, and you must bake your actions, as well as make sure they have a common parent bone if you’re using armature. Export Selected works better than Export All.
If you wanna check whether your mesh is right, you could get the DirectX Mesh Viewer, available along with the DirectX SDK from Microsoft to test if your mesh loads correctly in it.