# boolean_smtp_outlook_validate_settings

> Filters validation errors for an Outlook connection using a delivery mode not implemented by the free transport.

Filter · Tier B · Since 1.0.0

Fires only when the delivery mode is not `api` (a mode registered by an add-on through the `boolean_smtp_outlook_delivery_modes` filter). Return the validation errors for that mode, keyed by field name.

## Signature

```php
add_filter( 'boolean_smtp_outlook_validate_settings', $callback, 10, 3 );
```

## Parameters

| Name | Type | Description |
| --- | --- | --- |
| `$errors` | `array<string, string>` | Validation errors keyed by field name; empty until a listener adds to it. |
| `$mode` | `string` | The connection's delivery mode. |
| `$settings` | `array<string, mixed>` | Full connection settings being validated. |

**Returns** `array<string, string>` — The filtered errors.

## Fires in

- [app/Services/Mailer/Transports/OutlookTransport.php:124](https://github.com/booleanpress/boolean-smtp-src/blob/main/app/Services/Mailer/Transports/OutlookTransport.php#L124) — `BooleanSmtp\Services\Mailer\Transports\OutlookTransport::validateSettings()`

## Example

```php
add_filter( 'boolean_smtp_outlook_validate_settings', function ( array $errors, string $mode, array $settings ) {
    return $errors;
}, 10, 3 );
```