rich coexistence

About this tag
The rich coexistence tag covers Microsoft's evolving hybrid Exchange architecture, focusing on the transition from traditional on-premises Exchange servers to cloud-managed solutions. Recent discussions highlight two key developments: the mandatory migration to a dedicated Exchange hybrid app in Entra ID, driven by a high-severity vulnerability and enforced through scheduled EWS traffic blocks, and the introduction of cloud-managed remote mailboxes that allow organizations to retire their last Exchange server by transferring attribute authority to Exchange Online. These changes represent a significant shift in hybrid management, emphasizing security, automation, and reduced on-premises footprint for organizations maintaining coexistence between on-premises Active Directory and Exchange Online.

  1. Dedicated Exchange Hybrid App in Entra ID: Timeline, Steps, and Security

    Microsoft has begun a strict, time‑boxed push to move Exchange hybrid customers off a Microsoft‑managed shared service principal and onto a dedicated Exchange hybrid app in Entra ID — a change driven by a high‑severity hybrid vulnerability and enforced through short, scheduled EWS traffic blocks...
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    • certificate rotation cisa emergency directive 25-02 conditional access configureexchangehybridapplication cve-2025-53786 entra id ews block exchange hybrid graph migration hybrid apps hybrid configuration wizard on-prem exchange phased enforcement privilege rich coexistence service principal service principal cleanup setting override test oauth connectivity
    • Replies: 0
    • Forum: Windows News

  2. Cloud-Managed Remote Mailboxes: A Step Toward Retiring the Last Exchange Server

    Microsoft’s Exchange team has taken a decisive step toward finally letting organizations retire the last Exchange server in hybrid environments by adding cloud-managed remote mailbox support — a per-mailbox “flip-the-switch” that transfers Exchange attribute authority to Exchange Online while...
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    • active directory admin consent audit logs certificate management cisa-ed-25-02 cloud migration cloud writeback cloud-managed-remote-mailboxes compliance auditing configureexchangehybridapplication.ps1 cve-2025-53786 entra connect sync entra id ews block exchange hybrid exchange on-prem exchange online folder sync freebusy hybrid apps hybrid configuration wizard hybrid deployment identity management isexchangecloudmanaged last-exchange-server mailbox attributes mailtips microsoft education oauth on-prem ad patch management phase 1 preview phase 2 writeback phase-1 phase-2 powershell profile picture proxyaddresses rbac rich coexistence security hardening setting override writeback
    • Replies: 2
    • Forum: Windows News