Greylisting defends email users against spam. When the Greylisting is enabled, then the mail server will temporarily reject any email from a sender the server does not recognize. If the email is legitimate, the originating server will re-attempt after a delay. After sufficient time has elapsed, the server will accept the email.
1) Log in to the WHM.
2) Go to ‘Email’ tab on the WHM.
3) Select ‘Greylisting’ option.
4) Click on ‘OFF’ button in order to disable Greylisting.
5) By enabling Greylisting, we can see some options like Configuration Settings, Trusted Hosts, Common Mail Providers, and Reports. You should define Greylisting configuration settings. We can use default settings or set our own configuration settings. There is also an option which allows bypassing Greylisting for valid SPF records.
6) The second option is Trusted Hosts. Greylisting will never defer emails from entries on the Trusted Hosts list. Here we can define hosts that you typically receive an email from and you do NOT want Greylisting to affect. Click on to the New Trusted Hosts to add the IP address (or range) of the host. We can also add a comment for each entry. Click on Add button to add the hosts.
7) Go to Common Mail Providers. Here we can see a list of Common Mail Providers. By default, each common mail provider is trusted and automatically updates. If we are having problems with a common mail provider, then we can un-check the box. Click on Save button after updating the changes.
8) The last option is Reports tab. Here we can see the emails which are deferred as defined by its sender IP address, From Address and To Address.
If you need any further help please do reach our support department.