Hi, the corlib.dll that my Beta2 CSC produces seems to contain 0x301 for the coff_machine field. mono_image_open() barfs when it checks this field against 0x14c. Can anyone point me to the specs for this header? Better still, any idea what might be wrong? I'm using the latest cygwin, Windows XP and the Beta2 .NET. Thanks and regards, David Dawkins