Hello @Florian Eber
Have you tried putting the VHD on a different drive, for example C drive? I believe it was not recommended to manually add files into the VHD that are not part of the MSIX, That breaks the validity of the MSIX package and we will report no valid MSIX is present. I would recommend that on 1 of your machines you create a c:\share folder. Share it to everyone (read) put the package there and pass the path \shares\<name of msix image>
Hope this helps with your query,
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