@IDRISSI Hamid Thanks for reaching out to us!
Looking at the error message, it appears to be permissions issue. You may want to verify and confirm the permissions are set correctly.
- Make sure the Azure user account used to register the appliance has at least Contributor permissions on the subscription.
- Make sure the account has access to the key vault specified in the error message, and then retry the operation.
- If the issue persists, contact Microsoft support.
- Learn more about the required Azure roles and permissions.
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