Microsoft is investigating a widespread service issue causing authentication issues, email delays and failures, and various other issues for Exchange Online customers.
He first admitted this incident (tracked under EX1464935 in the admin center) at 17:30 UTC when it started surveying a stream of reports from users on social media.
According to the outage tracking service Downdetectortens of thousands of Exchange Online users are affected and are experiencing problems receiving email through Outlook and accessing the Exchange Online platform.
Microsoft says the list of symptoms includes:
- Delays or errors in sending or receiving email messages.
- Delays, errors, or incomplete results when searching for content in Exchange Online mailboxes.
- Authentication-related errors when accessing Exchange Online services.
- Difficulty accessing or performing actions within the Exchange administrative experience.
- Intermittent outages affecting mailbox operations and message delivery workflows.
Although the company has not yet revealed which regions are affected, it classified this outage as an incident, which is typically used to describe critical service issues with a noticeable impact on users.
”We have isolated a common failure pattern in affected Exchange Online requests that is related to protocol authentication and connectivity,” Microsoft added in the latest admin center update.
“We are analyzing service telemetry to identify the primary source of impact and validate potential remediation options. We are also continuing to assess the scope of the impact and monitor for additional affected scenarios.”
Microsoft has dealt with multiple Exchange Online outages in recent months, most recently in June when it mitigated a widespread service issue affecting the mail flow pipeline for customers in North America, Asia Pacific (APAC) and Europe.
In April, it also resolved Exchange Online mailbox access issues that intermittently affected Outlook mobile and macOS users for weeks, and an Exchange Online outage that prevented users from accessing their mailboxes through Outlook on the web, Outlook desktop, Exchange ActiveSync, and other Exchange Online connectivity protocols.
This is a developing story…
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