Sending safety: brakes and protections

Right now

At the top you see what the safety brake has stopped, if anything, with a button to review it. Below, the figures for the last 30 days: sent, bounced, unsubscribes and spam complaints, each next to its limit, and how many inactive contacts have been set aside.

And your mailboxes: whether they’re sending normally, whether they’re warming up (and which day they’re on) and how SPF, DKIM and DMARC came out in their last check.

The brakes

They stop sending by themselves when something goes wrong, before a problem turns into a bad reputation. They’re always on and can’t be turned off.

• Bounce brake. If more than 3% of a campaign’s last 200 sends come back because the address doesn’t exist, the campaign pauses. It’s usually an old or bought list.
• Unsubscribe brake. If more than 1% of a campaign’s last 200 sends end in an unsubscribe, the campaign pauses: those people aren’t interested in what they receive.
• Provider brake. If 50 emails from the last 7 days to the same email provider (gmail.com, hotmail.com…) still have no open or click 48 hours later, sending to that provider stops: they’re most likely landing in its spam folder. Any open counts, automatic ones too.
• Rejection brake. If a server rejects your emails because your server or your domain is on a blocklist, the mailbox pauses at once; for any other rule, at the third rejection in 24 hours.

The first two only judge a campaign once it has at least 100 sends.

Resuming

When a brake kicks in, the notice says what happened and with which figures, and nothing else goes out until you decide:

• A paused campaign: on its page, Resume sending. First, check where those contacts came from and what the email says to them.
• A paused mailbox: in its details, Resume the mailbox, once the cause is fixed. The details show what the server replied.
• A paused provider: Resume sending to… in the notice, here or in Settings › Sending, where all paused providers are listed. First, check the mailbox’s SPF, DKIM and DMARC.

On Home, I’ve checked it clears the notice. If you change nothing before resuming, the brake will most likely kick in again.

The other protections

• Inactive clean-up: anyone who doesn’t open or click anything in 8 emails over 120 days stops receiving them. You set it in Settings › Sending, and an inactive contact can be reactivated.
• Warm-up: a new mailbox starts with 20 emails on the first day and goes up over 14 days until it reaches its limit.
• Limits and pace: each mailbox has a daily and an hourly limit, below its provider’s, and sends are spread over your sending hours with a different pause between each one.
• Cap per email provider: at most 20 emails an hour to the same provider. Sending waits and carries on the next hour.
• Suppression list: unsubscribes, addresses that don’t exist, spam complaints and people who asked for their data to be deleted never receive anything again, even if you import them again.
• Easy unsubscribe: every email carries the unsubscribe link, the one-click unsubscribe that Gmail and Yahoo require and your legal footer.
• Spam check and domain checks: every email is checked against the rules filters use, and each mailbox’s details check SPF, DKIM, DMARC, the server’s reverse name and encryption.

To learn more

At the bottom of the page there are six short guides: how to stay out of spam, why use several mailboxes, bounced emails, unsubscribes and complaints, SPF, DKIM and DMARC in two minutes, and clean lists. The deliverability guide covers it all in detail, including how to set up each record with your provider.