Mailbox settings, and when a mailbox is Ready

Each mailbox has its own settings:

• Daily limit: how many campaign emails it sends a day. 30 is a safe number.
• Gap between emails: so emails go out steadily rather than all at once.
• Sender name and signature.

When a mailbox is used

A mailbox only sends campaigns when it shows Ready, which means:

1. it's connected,
2. it has warmed up, and
3. its domain has SPF, DKIM and DMARC.

If a mailbox isn't ready, its panel says which of these is missing. You can check a domain's records yourself with the free domain health checker.