[Mail] Hosted Exchange (SE) — service degradation
Hosted Exchange
User impact: Some customers may experience intermittent disturbances on Hosted Exchange (SE) — delayed mail delivery, Outlook/mobile sync issues, or difficulty accessing Webmail.
Context: Reports began this morning around 08:00 CEST, following the scheduled maintenance performed last night (30 May, 21:00 → 31 May, 04:38) on the Exchange SE cluster.
Current status: Our teams are actively investigating — reviewing DAG health, mailbox/transport services, client access paths (IMAP/POP/ActiveSync/Webmail) and related logs. Monitoring has been increased.
Further updates will follow as verification progresses.
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May 31, 2026 at 16:03 (UTC+02:00)
Investigation in progress. Following last night's Exchange SE maintenance, we received multiple user reports from around 08:00 CEST this morning. Teams are verifying cluster and service health (DAG, transport, client access). We will publish the next update as soon as we have more findings.
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Jun 1, 2026 at 12:06 (UTC+02:00)
Update — investigation continues. Our teams are still working on the Exchange SE instability reported this morning. We are actively pursuing stabilisation of the affected hosts.
Overnight we applied technical changes on several servers, including partial rollbacks of last night’s planned maintenance — intermittent issues persist for now.
Early analysis points to host-level instability (system services / hardware re-enumeration after reboot), not a defect in Exchange itself. The behaviour remains sporadic; we have not yet reproduced or isolated the exact trigger of the crashes.
Customer reassurance: when instability is detected, Exchange databases are dismounted and protected automatically — your data is safeguarded while services recover. We will keep you informed as stabilisation progresses.
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Jun 1, 2026 at 12:09 (UTC+02:00)
Update. We have fully rolled back the changes from Saturday evening’s planned maintenance on the affected Exchange SE hosts. This has not resolved the issue: intermittent disturbances continue, and we have not yet identified the exact cause nor implemented a lasting fix.
Our teams remain actively engaged — ongoing checks, tests and troubleshooting on the underlying host-level instability. The behaviour remains sporadic and not reproducible on demand at this stage.
Exchange is impacted as a consequence of this host instability, without an Exchange-specific fault identified. When instability occurs, databases are automatically protected (dismounted) to safeguard your data. We are still working on it — further update to follow.
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Jun 1, 2026 at 19:13 (UTC+02:00)
Update. Verification and troubleshooting on the Exchange SE hosts will resume from 21:00 CEST (19:00 UTC) this evening. Scope: host health checks, storage/access-path validation, DAG/transport/service state review, and log correlation from prior instability events.
Incident remains open — root cause not yet confirmed. Further update after this verification cycle.