hashicorp/packer · error

Bad script '%s': %s

Error message

Bad script '%s': %s

What it means

During PowerShell provisioner Prepare, each configured script path is checked with os.Stat. If a path cannot be stat-ed (missing file, bad permissions, or invalid path), the provisioner reports "Bad script '%s': %s" embedding the underlying OS error. Prepare returns accumulated errors so template validation fails before any build runs.

Source

Thrown at provisioner/powershell/provisioner.go:270

			log.Printf("Using script default execute command %s", p.config.ExecuteCommand)
		}

	}

	if p.config.ElevatedExecuteCommand == "" {
		if p.config.Inline != nil && len(p.config.Scripts) == 0 {
			p.config.ElevatedExecuteCommand = p.defaultExecuteCommand()
			log.Printf("Using inline default elevated execute command %s", p.config.ElevatedExecuteCommand)
		} else {
			p.config.ElevatedExecuteCommand = p.defaultScriptCommand()
			log.Printf("Using script default elevated execute command %s", p.config.ElevatedExecuteCommand)
		}
	}

	for _, path := range p.config.Scripts {
		if _, err := os.Stat(path); err != nil {
			errs = packersdk.MultiErrorAppend(errs,
				fmt.Errorf("Bad script '%s': %s", path, err))
		}
	}

	// Do a check for bad environment variables, such as '=foo', 'foobar'
	for _, kv := range p.config.Vars {
		vs := strings.SplitN(kv, "=", 2)
		if len(vs) != 2 || vs[0] == "" {
			errs = packersdk.MultiErrorAppend(errs,
				fmt.Errorf("Environment variable not in format 'key=value': %s", kv))
		}
	}

	if p.config.ExecutionPolicy > 7 {
		errs = packersdk.MultiErrorAppend(errs, fmt.Errorf(`Invalid execution `+
			`policy provided. Please supply one of: "bypass", "allsigned",`+
			` "default", "remotesigned", "restricted", "undefined", `+
			`"unrestricted", "none".`))
	}

View on GitHub (pinned to eb36e3c3e4)

Solutions

1. Correct the `scripts` entry in the template so each path exists; test with `ls <path>`/`Test-Path <path>` in the same directory packer runs from.
2. Use absolute paths or template variables ({{path_root}}/packer start-dir) so relative resolution is not cwd-dependent.
3. Verify file permissions allow reading by the user running packer.
4. If generating scripts dynamically, use `inline` instead of `scripts` so the provisioner creates the file itself.

Example fix

// before
"scripts": ["./scrpts/bootstrap.ps1"]
// after
"scripts": ["./scripts/bootstrap.ps1"]

// Go, before calling Prepare
for _, p := range cfg.Scripts {
    if fi, err := os.Stat(p); err != nil {
        return fmt.Errorf("script %q unavailable: %w", p, err)
    } else if fi.IsDir() {
        return fmt.Errorf("script %q is a directory", p)
    }
}

// Go
if err := prov.Prepare(cfg); err != nil {
    var pathErr *os.PathError
    if errors.As(err, &pathErr) {
        // fix or remove the offending script path in cfg.Scripts
    }
    return err
}

When it happens

Trigger: Calling Provisioner.Prepare with config.Scripts containing a path that does not exist, points to a directory, or is otherwise unstatable (os.Stat returns non-nil err).

Common situations: Typo in the script path; relative path resolved against a different working directory (packer run from another cwd); script deleted or moved after writing the template; Windows path separators mixed up; path points to a directory instead of a .ps1 file.

Related errors

• Environment variable not in format 'key=value': %s
• Invalid execution policy provided. Please supply one of: "by
• %d is an invalid Trace level for `debug_mode`; valid values
• Error stating powershell script: %s
• Only one of script or scripts can be specified.

AI-assisted analysis of hashicorp/packer@eb36e3c3e4 (2026-09-05). Data as JSON: /api/errors/f9dd363eed8075bd. Report an issue: GitHub.