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. 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. Released: October 2026 Exchange Server Security Updates We have released October 2026 Security Updates for Exchange Server SE. Exchange Server 2019 and 2016 ESU updates only. Exchange Online EWS application stopped working? Do this. This blog post contains exact steps to temporarily unblock your blocked EWS applications (until April 2027). EWS Deprecation Is Here – What This Means To You EWS deprecation in Exchange Online is starting today. Learn the details of what happens next. Released: September 2026 Exchange Server Security Updates We have released Security Updates for Exchange Server SE. Exchange Server 2019 and 2016 ESU updates only. Trust DigiCert Global Root G2 Certificate Authority to Avoid Exchange Online Email Disruption We wanted to let you know of an upcoming change in certificates trusted by Exchange Online. Introducing more control over Direct Send in Exchange Online Read about a new feature that gives you more control over Direct Send in Exchange Online. Notes from the field: testing EWSAllowedAppIDs safely We wanted to share some tips on how to test EWSAllowedAppIDs (EWS AppID allow list). Announcing Period 2 Exchange 2016/2019 Extended Security Update (ESU) program We created a Period 2 ESU for Exchange customers who need extra time to migrate to Exchange SE.
