In 04-packer.md, the step "Create custom machine image", I got the error > googlecompute: google: could not find default credentials. See https://developers.google.com/accounts/docs/application-default-credentials for more information. After googling, I found this link https://www.packer.io/docs/builders/googlecompute.html and it help me to fix the above error. Step to fix : 1. "Compute Engine Service Account" need to be created 2. Export the JSON file 3. Then add a option "account_file" into addit-base-image.json Please let me know if I am missing any step that causes this error. Thanks Mark