I've just installed feynmf package and tried working with a standard example. I'm working with MikTeX 2.9 on Windows. The compilation worked fine and I got the diagram in the PDF, but when changing the code nothing happens. It seems as if there is some problem with the rights concerning overwriting the already created diagram files.
There was another question similar to this one and the answer was simply "rerun mf after a change in a diagram".
I have already tried but I still got the same problem. I can't overwrite the already created diagram and I always get the same diagram.
The way I rerun mf is: mf "\mode=localfont; input diag1", where (of course) "diag1" is the fmffile name in .tex source.
Thank you very much!