This article enumerates possible reasons why Exchange Online and Azure Rights Management (Azure RMS) cannot be provisioned in Cloud App Security (CAS). Other services (SharePoint, OneDrive, Microsoft Teams) are successfully provisioned and the issue still happens even if Global Administrator account is used for provisioning.
For Exchange Online and RMS provisioning, make sure that the Global Account has not enabled the security settings below:
- Multi-factor Authentication (MFA)
- Security Default
- Special conditional access rule configuration
After verification, you may retry to provision the services again.
If you still encounter error after following steps mentioned, you can contact Trend Micro Technical Support for further assistance.