[US/EU] Elevated Errors for Microsoft Message Send, Draft, and Read Operations

Update timeline

1. investigating Aug 31, 2026, 09:39 PM UTC

   We are seeing elevated error rates affecting message sending, drafts, and message and folder retrieval for a subset of Microsoft-connected accounts in the US and EU regions. Some requests may fail or require retrying. Microsoft is also reporting a service degradation that appears consistent with the behavior we are observing: https://status.cloud.microsoft/ Initial evidence indicates that this issue is related to the ongoing Microsoft service degradation. We are continuing to assess the impact to Nylas customers and will provide additional updates as more information becomes available.

2. identified Aug 31, 2026, 10:25 PM UTC

   We have confirmed that the elevated error rates are related to an ongoing Microsoft Exchange Online service degradation affecting Microsoft-connected accounts. Microsoft is tracking the incident as EX1464935. Customers with Microsoft-connected accounts may experience failures when sending messages, creating or accessing drafts, or retrieving message and mailbox data in the US and EU regions. Some requests may require retrying. This issue is limited to Microsoft-connected accounts and does not affect other providers. We are continuing to monitor Microsoft's service degradation and its impact to Nylas customers. Microsoft's public service update: https://x.com/MSFT365Status/status/2094455556454920701

3. identified Sep 01, 2026, 12:51 AM UTC

   According to Microsoft's service health updates, Microsoft has begun deploying broader mitigation for the ongoing Exchange Online service degradation and is reporting gradual recovery across affected services. Microsoft has indicated that mail flow is expected to be among the first areas to recover. We are continuing to monitor the impact to Microsoft-connected Nylas accounts and will provide another update as recovery progresses. This issue remains limited to Microsoft-connected accounts and does not affect other providers.

4. monitoring Sep 01, 2026, 02:32 AM UTC

   According to Microsoft's service health updates, mitigation has been deployed for the ongoing Exchange Online service degradation and Microsoft continues to report recovery across affected services. Nylas monitoring confirms that Microsoft-connected message send, draft, and read operations have substantially recovered across both the US and EU regions. The provider-related errors observed during the incident have declined to near-normal levels, and request performance continues to stabilize. We will continue to closely monitor performance and confirm that recovery remains sustained before considering this incident resolved.