Greylist
- Click 'SMTP' > 'Greylist' in the left menu.
- Greylisting is another form of spam control whereby Secure Email Gateway will temporarily reject mail from senders it does not recognize. Instead, it will send a 'try again later' message to the sending mail server.
- Upon receiving this message, legitimate mail servers will try to resend the mail after a delay. Secure Email Gateway will accept the resent mail providing it does not fall foul of its other filters.
- However, because of the prohibitive cost of re-sending millions of mails, spam servers are unlikely to perform this simple resend This means greylisting can be very effective at blocking large amounts of spam at source.
- You have the option to disable greylisting entirely, or you can specify IP addresses/domains as exceptions (so CSEG will accept mail from them on first contact).
See 'Greylist
Ignored IP Addresses/Domains' for how to add domains, networks
and IP addresses to Greylist ignored list.
