SmarterMail Help

Antispam | Greylist Filters

SmarterMail's antispam options include greylisting which is a very effective method of spam blocking that comes at a minimal price in terms of performance. When enabled, the system will keep track of the sending IP address, sending email address and recipient's email address for every message received. If an incoming message has a combination of a sending IP, sending address and recipient address that has not previously been seen, it will return a temporary failure to the sending server, effectively saying, “Try again later.” Valid servers will retry the email a short time later, which would be permitted. Spammers, on the other hand, typically create scripts that bombard your server with emails, and they rarely retry on temporary failures. When these messages are bounced back because of greylisting, they are typically not retried, therefore reducing the amount of spam that your customers receive.

As part of the greylisting configuration on the Antispam | Options tab, administrators can choose to greylist messages from everyone, greylist messages from the specified countries / IP addresses, or greylist messages from everyone except the specified countries / IP addresses. If the greylisting 'Applies To' setting on the Antispam | Options tab is set to 'Only specified countries / IP addresses' or 'Everyone except specified countries / IP addresses', administrators will use the Greylist Filters tab to add those exceptions / limitations.

To add greylisting filters based on the sender's country or IP address, log in to SmarterMail as an Administrator and click on the Settings icon. Then click on Antispam in the navigation pane and click on the Greylist Filters tab. To add an IP address or country code, click New.

  • Filter Type - Select the type of filter you would like to add: IP Address or Country Code.
  • IP Address - If the filter type is set to IP Address, enter the IP address that should bypass greylisting / be greylisted.
  • Country Code - If the filter type is set to Country Code, select a country code from the list. The greylisting exception / limitation will apply to all messages that are identified as coming from an IP address matching that country.