Lean CLI: Error: Invalid value for '--data-provider-historical': 'Local' is not one of . (Cannot Run Any Backtest)

[Bluesoul111]

Hello QuantConnect Team,

I am experiencing a persistent error with the Lean CLI on Windows when running any backtest (e.g., lean backtest .). The error is:

Error: Invalid value for '--data-provider-historical': 'Local' is not one of .

What I have already tried:

• No lean.json in my project, workspace, or user profile directory.
• No .lean or .lean-cli hidden folders anywhere.
• No "data-provider-historical" entry in any config.json.
• No relevant environment variables (Get-ChildItem Env: | Where-Object { $_.Name -like "*LEAN*" } returns nothing).
• No global config files in %APPDATA%, AppData\Roaming, or AppData\Local.
• Never used pipx to install Lean.
• Fully uninstalled and reinstalled Lean CLI (pip uninstall lean -y and pip install lean), now running version 1.0.218.
• Ran lean config reset.
• Started a completely new project with lean create-project, but the error still appears.
• All commands are run with no extra flags, just lean backtest . or lean backtest Algorithm.
• Purged all possible config, cache, and hidden files from user, appdata, and project directories.
• Checked the registry for Lean-related keys (none found).
• Cleaned Python site-packages of any lean* or quantconnect* folders.
• Reinstalled Lean CLI in a new virtual environment.
• Tried running in a new temp directory with a fresh project.
• Tried running with LEAN_DEBUG=1 and --verbose (no extra debug output).
• Tried downgrading Lean CLI to earlier versions.
• Tried on a clean Docker image.

System Info:

• OS: Windows
• Python: (Anaconda, 3.9, venv: lean-env)
• Lean CLI: 1.0.218
• Default shell: PowerShell

The error persists in all cases, even with a clean environment and new project.
It appears that the CLI is injecting 'Local' for --data-provider-historical internally, and no valid providers are registered.

Please advise:

• Is there any hidden global state, cache, or registry entry that could cause this?
• Is this a known bug in the current CLI?
• How can I fully reset or repair the CLI so that it uses the default data provider and allows local backtests to run?

Thank you for your help!

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