Office Online Server (OOS) retirement announced — what Exchange on‑prem customers need to know and do
By WindowsForum IT Desk — Oct 21, 2025
Microsoft has announced that Office Online Server (OOS) will be retired and reach end of support on December 31, 2026. For organizations that run Exchange...
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...