User ManualEmail Discussion Group User Guide TroubleshootingHow to configure Mimecast to allow Mailing List emails

How to configure Mimecast to allow Mailing List emails

Mimecast specializes in email security for Microsoft Exchange and Microsoft Office 365.

Why Emails are Blocked

Mailing Lists are a special challenge for software that is trying to stop spam and malware.

Traditionally, mailing lists keep the original sender of the message in the From: header. However, the email is sent from the mailing list server, not from the original sender's ISP.

Some anti-spam settings will reject emails for this reason.

Mimecast Details

Mimecast is complicated. There are many places within Mimecast to set policies. Two ways to set up a policy allowing mailing list emails are described below.

Option 1

  • Navigate to the Gateway / Policies Tab.
  • The policy needs to be created in the “Permitted Senders” category, to allow receipt from your bulk mail provider.
  • Add's IP addresses to the "Source IP Ranges" field. IP addresses:

See example below to create a new policy:

Option 2

See another example below to create a new policy. This is different way of accomplishing the same result as above.