Hi
there's an undocumented option -xx (double x) in cdimage.exe program.
-xx an extension of -x
When used with -xx cdimage.exe generates checksum for image header
Usually this DWORD resides at 0x8FFC of ISO-image file and makes CRC32 of first 0x9000 bytes to be equal 0xFFFFFFFF. But the position of this checksum may differ
Microsoft use this option when creating iso-images so this checksum's present on it's isos