Hi, @Mirko
Thank you for posting in Microsoft Q&A forum.
Your OSDisk is now = J:
When running the command: dism.exe /Image:J:\ /Apply-Unattend:J:\Windows\Panther\Unattend.xml /ScratchDir:J:\MININT\Scratch, it failed.
We may review dism.log for more details, the DISM log file can be found at X:\windows\Logs\DISM\dism.log.
Also check smsts.log, it is is located at X:\windows\TEMP\SMSTSLog\SMSTS.LOG.
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