MeshCAM generates files as *.m but Mach 3 doesn't recognize it as g-code?  Where do I go from here?

In MeshCAM, when you click "Save Toolpath", below the filename, under "Save as type", you need to select a Mach3 post processor. It looks like you are using the Anilam post processor, which is the first one in the list.

Thanks Gerry.  Yeah saving it as a tap file works OK