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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.
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...
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...