Microsoft’s Exchange team published a short but important Hotfix Update (HU) rollup for September 2025 that is aimed at fixing a non‑security issue in earlier updates and, crucially, preserves support for the dedicated Exchange hybrid application workflow introduced earlier in 2025 — the update...
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cu14
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cve-2025-53786
dedicated hybrid app
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ews
exchange hybrid
exchange server
exchange server 2016 cu23
graph permissions
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hotfix update
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migration to dedicated hybrid app
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september 2025
service principal
windows update
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...