Enable Greylisting: Check this option to enable greylisting.
Do Not Greylist Good Senders: This option tells Alligate to not greylist messages coming from an IP address that is listed in MXRate as a "Good Sender". MXRate maintains a list of over 80,000 "good senders" or trusted sources known to send legitimate email. An MXRate subscription is required.
Allow If Resent In x Minutes: This option instructs Alligate to allow messages through that retry within "x" minutes after being initially greylisted.
Sender Must Resend in x Hours: This setting tells Alligate to reject messages that do not retry delivery within "x" hours after the initial message was sent that was in fact greylisted.
Remove If Inactive for x Hours: This option removes records in the greylisting database that have not sent messages to Allligate within "x" hours.
Tarpit initial greylisting connections for x Minutes: This option tells Alligate how long it should tarpit a connection where the remote server has never tried to send a message to this server before, and greylisting is enabled.