> ## Documentation Index
> Fetch the complete documentation index at: https://docs.hasmcp.com/llms.txt
> Use this file to discover all available pages before exploring further.

# How do I troubleshoot a 401 Unauthorized error?

> Fixing broken bearer authentication layers securely.

# Troubleshooting a 401 Unauthorized

A `401 Unauthorized` clearly indicates that your API request completely lacks valid authentication credentials. HasMCP physically rejects the request before it even reaches the core execution engine.

## Common Causes

1. **Missing Bearer Header**: You fired an API request without including the standard `Authorization: Bearer <token>` HTTP header.
2. **Invalid Token**: The token string you provided is structurally flawed, explicitly copy-pasted incorrectly, or fundamentally does not exist.
3. **Expired Token**: The Server Token was previously valid but has explicitly expired based on your organization's security lifecycle policies.
4. **Revoked Token**: An administrator explicitly revoked the Server Token you are actively using from the HasMCP Dashboard.

## Resolution Steps

1. **Log in to HasMCP**: Navigate to the exact Server Dashboard associated with your capability pipeline.
2. **Generate a New Token**: Click "Create Token" to systematically instantiate a fresh cryptographic key.
3. **Update Your Script**: Inject the newly copied token seamlessly into your testing script or local MCP Client configuration. Ensure the `Bearer ` string prefixes the token in your headers.