Hello,

This normally means the setting for "Index of the volume to expand" has been set incorrectly. This is normally 0 or 1 but can be higher depending on the partition table for the VHDx file.

Kind Regards,

Trevor Robinson

If it is windows:
For generation 1 - Index of the volume to expand is 1
For generation 2 - Index of the volume to expand is 0

@Trevor and @Genadij,
Thank you for your reply, I have tried those options but still getting the same Error for some reason.
If I avoid unattend.xml file (at the end of the path) it works which I believe it's wrong process.
Any other suggestions!

Hi,
I managed to solve this error. This error was happened due to unattent.xml file.
Thanks