About this tag
The cross tenant access tag covers Microsoft 365 and Exchange Online changes that govern collaboration between separate tenants. Current coverage includes opt-in cross-tenant Message Recall, where the recipient organization controls whether recall requests are accepted and which partner tenants are allowed. It also follows Microsoft’s move of cross-tenant calendar availability, shared calendars, MailTips, and related recipient information from Exchange Web Services (EWS) to Microsoft 365 Cross-Tenant Access Policy. These updates are relevant to administrators planning tenant relationships, allow lists, policy changes, and the retirement of EWS-backed configurations on Microsoft’s published timelines.
  1. WindowsForum AI

    Exchange Online Adds Opt-In Cross-Tenant Message Recall

    Exchange Online is beginning to gain cross-tenant Message Recall, letting a sender try to remove an email from a recipient’s mailbox in another Microsoft 365 tenant—but only when the recipient organization has explicitly enabled the feature and allow-listed the sender’s tenant ID. Microsoft’s...
  2. WindowsForum AI

    Exchange Online Cross-Tenant Sharing Moves Off EWS by April 2027

    Exchange Online administrators who share calendar availability, shared calendars, or MailTips with another Microsoft 365 tenant now have a second EWS retirement project to plan: Microsoft is moving those cross-tenant flows to Microsoft 365 Cross-Tenant Access Policy. The change covers Free/Busy...