Exchange Online ETRs to stop supporting DLP policies

Over the past few years, Microsoft have helped many customers migrate their Data Loss Prevention (DLP) policies using Exchange Transport Rules (ETRs) in the Exchange admin center (EAC) to DLP policies in the Microsoft Purview compliance portal. As part of this process, they disabled the creation and editing of DLP rules using ETRs in the EAC over a year ago.

Microsoft have announced the following in their Blog.

Today, we are announcing we are discontinuing support for DLP rules within Exchange Online ETRs. Beginning in early August 2023, we will no longer support ETRs linked to DLP policies. Customers should re-validate any existing legacy DLP rules, and either consolidate or migrate them to the compliance portal (if not done already). To migrate DLP-related ETRs to DLP policies, we recommend using the migration wizard to bring over policies to the compliance portal.Additional advantages of migrating your DLP rules to the compliance portal include:

• Unified admin console
• Single policy across all workloads (Exchange, SPO, ODB, Teams, Devices, MDA, etc.)
• Near real-time alerts
• Quick navigation to other compliance product features and capabilities
• More advanced classification and labelling
• Rich built-in alerting and incident management experience

Starting in early August 2023, any rules that match the criteria for an ETR rule linked to a DLP policy that still exist in the EAC will no longer be evaluated and will stop executing (as if the rule is disabled). In these cases, you will see the following new columns in the EAC and PowerShell stating the rules are no longer supported with the reasoning. If you’ve already migrated your DLP rules to DLP policies in the compliance portal, please ensure these ETR rules have been deleted in the EAC as this will help you better manage your non-DLP ETR rules and clean up your environment.

Migration Process and Playbook

To accelerate the migration process, the compliance portal has a built-in wizard to help migrate your policies with a few clicks. The entire process is explained in the playbook at Migrating from Exchange Transport Rules to Unified DLP – The complete playbook.

Exchange Online Transport Team and Microsoft Information Protection Data Loss Prevention Team