Cross-Tenant Message Recall and Duplicate DDG Detection Enhance Exchange Online Messaging

Cross-tenant message recall.

Last week, the Exchange development team announced two interesting developments. Stopping duplicate dynamic distribution groups and cross-tenant message recall. Preventing tenants from creating duplicate DDLs saves service resources and might make tenants easier to manage. The real value is in cross-tenant message recall, which solves a problem by allowing users to recall messages delivered outside their tenant. The facility only works if the receiving tenant allows, but nothing can be done for messages delivered outside Microsoft 365.

Exchange Online Restricts the Number of Dynamic Distribution Groups

Limit for dynamic distribution groups

Exchange Online is imposing a new tenant-wide limit of 3,000 Dynamic Distribution Groups. Few tenants might be affected, but the question might be asked why Microsoft is limiting DDGs at this point. Is it a cunning plan to prompt people to use dynamic Microsoft 365 groups instead? Or are some tenants abusing DDGs in weird and wonderful ways? Who knows, but the limit applies from early April 2025.