# Settings reference

> Every setting on the BooleanSMTP Settings screen, grouped by its card, with the default value and where it's explained.

Go to **BooleanSMTP → Settings** in your WordPress admin. These settings apply to your whole site — a
connection's own fields, like its provider credentials or its From address, are edited on the connection
itself, under **Mailers**.

![The Settings screen: the Delivery & Reliability, Logging & Retention and Testing & Content cards.](../../assets/screenshots/settings.webp)

## Delivery & Reliability

| Setting | What it does | Default | Explained on |
| --- | --- | --- | --- |
| **Default Connection** | The connection used when nothing more specific claims the message. | System Default (PHP Mail) | [How a connection is chosen](/sending/) |
| **Fallback Connection** | Retried once, immediately, when the primary send fails. | On, no connection chosen | [Fallback and retries](/sending/fallback-and-retries/) |
| **Retry on other connections** | Queues a still-failing send for up to 2 more retries on your other active connections. | On | [Fallback and retries](/sending/fallback-and-retries/) |

## Logging & Retention

| Setting | What it does | Default | Explained on |
| --- | --- | --- | --- |
| **Log All Active Emails** | Keeps a delivery record, visible on Email Logs, for every outgoing email. | On | [Log retention](/logs/retention/) |
| **Log mailer resolution to PHP error log** | Writes one JSON line per email to your server's PHP error log, showing which connection and transport were chosen. | Off | [Log retention](/logs/retention/) |
| **Retention Period** | How long email logs are kept before BooleanSMTP clears them automatically. | 30 days | [Log retention](/logs/retention/) |

## Testing & Content

| Setting | What it does | Default | Explained on |
| --- | --- | --- | --- |
| **Email Simulation Mode** | Records outgoing emails to Email Logs instead of sending them. | Off | [Simulation mode](/sending/simulation-mode/) |
| **Auto-generate Plain Text** | Creates a plain-text alternative for an HTML email, which improves compatibility with some inboxes. | On | — |
| **Test Email Activity Console** | Shows the SMTP handshake on the Test Email page when you send a test. | Off | — |

## Next steps

- [How a connection is chosen](/sending/)
- [View email logs](/logs/)
- [Troubleshooting](/troubleshooting/)