Email are not sent
Make sure the network flow to your smtp server is open.
You can check you smtp setting by sending a test email. Next to the smtp settings, you have a test button.
Note
Alerts are sent by the Integrator the monitor’s probe reports to (by the probe itself only when it has no Integrator endpoint).
Reports are sent from the webserver.
The SMTP settings are set once on the webserver; saving them pushes them to every enabled Integrator.
A test email that works proves the SMTP settings from the webserver’s host only. When alerts still do not arrive, see Alert notifications → Email and Alert notifications → Troubleshooting.