Hi @Samuel Yang Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
Even though the command is in public preview, it still works to generate the update files. The message Command group 'iot du update init' is in preview and under development. Reference and support levels: https://aka.ms/CLI_refstatus
is just to indicate that the command is still in preview and some features are still being developed and tested.
The command does not have option to specify the output directory path to save the file. It is most likely saved under the directory where you have executed the command from. In your case, it is C:\Users\samue
. Please look for the file under this directory and you should be able to find it.
Hope this helps! Please let us know if you need any further assistance on this.
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