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

# E1601 — Runner already registered

> Runner already registered

# E1601 — Runner already registered

| Property     | Value                         |
| ------------ | ----------------------------- |
| **Code**     | `1601`                        |
| **Slug**     | `E1601`                       |
| **Category** | `runner` (Runner / Consensus) |
| **CIP**      | CIP-2                         |

## What happened

Runner already registered.

## Why it happened

The runner address is already registered in the runner registry.

## How to fix

Use update or unregister to change the runner's state.

## Receipt example

```json theme={null}
{
  "code": 1601,
  "slug": "E1601",
  "category": "runner",
  "what": "Runner already registered",
  "fix": "Use update or unregister to change the runner's state.",
  "docs_url": "https://docs.cowboy.inc/errors/E1601"
}
```

***

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