On Tuesday, December 11, 2012 2:23:46 AM UTC-5, NBM wrote: > Having written a lot of code on M8, I recently switched to M9 and tried to > > run the code which starts by loading an .mx file written by M8, but M9 wouldn't read it saying that it was written on another machine. This is a major incompatibility issue between M8 and M9. Fortunately I kept my M8 installation, so for now, M9 is useless to me. > > Please a solution.
Keep V8 around, or convert your MX files to WDX.
Current and previous Mathematica documentation says that MX files are not portable across versions of Mathematica, i.e.
MX files cannot be exchanged between different operating systems or versions of Mathematica.