List of Mimecast inbound mail servers DNS MX records for Europe, UK, US, Canada and other global regions.
How to set up DKIM in Mimecast (with Office 365). Create a DNS Authentication Outbound Definition and Policy. Add DNS record for DKIM selector and verify DKIM.
How to configure Mimecast Personal Portal SAML Single Sign On (SSO) using Azure Active Directory as an identity provider
How to change the frequency of Mimecast email notifications and digest emails by modifying the Digest Sets policy definition.