1. MX的问题
The MX record for your domain is not configured correctly. If GFI MailEssentials should be receiving emails from the internet, the MX record should point to the IP address of the machine running GFI MailEssentials.
2. email经过其他网关的问题
If inbound emails are passing through another gateway, ensure that you have configured the mail server running on the other gateway to forward inbound emails through GFI MailEssentials