Most RecentNewest TopicsMost LikesMost ViewedExchange servers may become unstable after installation of October 2026 Windows updates More information related to issues that some Exchange servers might experience after installation of October 2026 Windows updates. Released: November 2026 Exchange Server Security Updates We released November 2026 Security Updates for Exchange Server SE. Cross-tenant Free/Busy, MailTips, and Calendar Sharing are moving to Cross-Tenant Access Policy We wanted to provide information related to migration of existing Exchange Online Organization Relationships to the new sharing model. Exchange Online EWS, Your Time is Almost Up We wanted to provide an update on Exchange Online EWS deprecation. Throttling and Blocking Email from Persistently Vulnerable Exchange Servers to Exchange Online As we continue to enhance the security of our cloud, we are going to address the problem of email sent to Exchange Online from unsupported and unpatched Exchange servers. Update on Transport Enforcement System in Exchange Online We are going to delay the release of the report to the first set of customers by 1 month. Understanding the new 100 GB mailbox entitlement for Microsoft 365 Business suites We wanted to show Administrators how recent mailbox quota changes for Microsoft 365 Business suites will apply to their users. Updated Exchange Online SMTP AUTH Basic Authentication Deprecation Timeline We wanted to provide the updated Exchange Online SMTP AUTH Basic Authentication Deprecation Timeline. Take control of your EWSAllowedAppIDs list before EWS access changes We wanted to provide additional guidance on how admins should use the EWSAllowedAppIDs allow list during EWS deprecation. Now available: OAuth authentication for on-premises Exchange mailbox migrations to Microsoft 365 MRS migrations now support OAuth!
