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Outlook Mobile Sync Delays Reported in Hybrid Modern Authentication Environments

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1 unique sources, 1 articles

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Microsoft is addressing an Exchange Online issue affecting Outlook mobile users with Hybrid Modern Authentication (HMA). The problem, tracked as EX1137017, began on August 17, causing email and calendar access issues due to 12-hour sync delays. The issue stems from a recent service change intended to improve mailbox sync efficiency. Microsoft has deployed a fix to prevent syncs from entering a quarantine state, but the exact number of affected users and regions remains undisclosed. Additionally, Microsoft is investigating a separate issue affecting Microsoft Teams users, resulting in blank screens and freezes during meetings and calls on the desktop app.

Timeline

  1. 23.08.2025 17:15 1 articles · 1mo ago

    Outlook Mobile Sync Delays Reported in Hybrid Modern Authentication Environments

    Microsoft identified an issue affecting Outlook mobile users with Hybrid Modern Authentication (HMA). The problem, tracked as EX1137017, began on August 17, causing email and calendar access issues due to 12-hour sync delays. The issue stems from a recent service change intended to improve mailbox sync efficiency. Microsoft has deployed a fix to address the sync delays, but the exact number of affected users and regions remains undisclosed.

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