Email warnings — bounces, automatic disabling, expiring certificate

The system monitors sending health and issues three kinds of warnings—all to company administrators.

1. Rising bounces

A high-priority warning when a series of bounces occurs during one checking cycle. This is an early signal: nothing has been disabled yet, but the trend is bad.

Response: find out where the addresses came from. Most often, they are in an old, uncleaned contact database.

2. Automatic account disablement

The most important mechanism in this article:

If an account sent at least 20 messages in the last hour and its bounce rate exceeded 10%, the account is disabled automatically, and administrators receive a critical-priority notification.

The account will not resume by itself. It remains disabled until manually enabled.

To restore it:

1. Find the cause—usually an outdated address list or errors in recipient data.
2. Clean the source of invalid addresses.
3. Check the exclusion list (Exclusion list — addresses we do not send to).
4. Enable the account again—remember that activation rechecks incoming-mail configuration (Email and SMS accounts — sending configuration).

This protects the sender address's reputation. Email providers lower their trust in senders with high bounce rates—and then valid messages stop arriving too.

3. Expiring certificate

A daily check warns 14 days before the mail server certificate expires. An already expired certificate is reported as critical. Repeated warnings are muted for a day.

Sender-address warm-up

There is also a warm-up throttle: when bounces exceed 2%, increasing the sending volume is paused. A new sender address is gradually brought up to full capacity.

Messages held at this stage appear in the log as skipped, with a warm-up reason (Sending log — what happened to a message).

Where to see this

Warnings go to administrators' notification bell. Account health is visible on the accounts tab, and the bounce rate in statistics (Sending log — what happened to a message).

It is worth checking it before an alert arrives.