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Outlook Mobile Users Experience Email Access Issues Due to Exchange Online Sync Delays

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πŸ“° 1 unique sources, 1 articles

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Microsoft is addressing an ongoing issue affecting Outlook mobile users who use Hybrid Modern Authentication (HMA). The problem, tracked as EX1137017, causes 12-hour sync delays and prevents users from accessing their email and calendars. The issue began on August 17 and is due to a recent service change designed to improve mailbox sync efficiency. The problem affects users who encounter transient failures, leading to sync jobs being quarantined and delayed. Microsoft has deployed a fix to prevent syncs from entering the quarantine state. The extent of the impact, including affected regions and customer numbers, remains undisclosed. Additionally, Microsoft is investigating an issue with Microsoft Teams desktop app, causing blank screens and freezes during meetings and calls. This issue may affect users with Intel driver versions 32.0.101.69xx.

Timeline

  1. 23.08.2025 17:15 πŸ“° 1 articles Β· ⏱ 24d ago

    Outlook Mobile Users Experience Sync Delays Due to Exchange Online Issue

    On August 17, 2025, Outlook mobile users began experiencing email access problems due to a service change in Exchange Online. The issue, tracked as EX1137017, causes 12-hour sync delays for users with Hybrid Modern Authentication (HMA). Microsoft has deployed a fix to prevent sync jobs from entering a quarantine state. Additionally, Microsoft is investigating an issue with the Microsoft Teams desktop app, causing blank screens and freezes during meetings and calls. This issue may affect users with Intel driver versions 32.0.101.69xx.

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