# EM_FIELD_INVALID

A value in the run's execution settings is not one Forge recognises.

## What happened

One of the values in this run's execution settings is not one Forge recognises. Before a run starts, the engine settles every setting it depends on, and a setting that cannot be settled ends the run with this code without testing anything. The engine's own text is in `detail.reason`.

## What to do

Check each field in Execution for a typed-in value where a chosen one belongs, then save again.

## Example

```json
{
  "status": "failed",
  "error": {
    "code": "EM_FIELD_INVALID",
    "message": "The engine refused this run's settings before it started.",
    "detail": {}
  }
}
```

The reply also carries `detail.reason`, left out of this sample.