Anthropic has acknowledged an ongoing service disruption affecting its Claude AI platform, with users facing authentication problems while trying to access Claude.ai and Claude Code. The company has confirmed that it is investigating elevated errors across multiple services, including its developer platform, as complaints from users continue to emerge.
In an update published on its official status page on November 13, Anthropic said it was investigating an issue affecting users attempting to authenticate with Claude.ai and Claude Code. The update was posted at 9:58 UTC (3:28 PM IST). The company said it would share more information as soon as it had an update but did not provide an estimated resolution time.
The disruption comes amid a spike in user complaints reported by Downdetector. The outage-tracking platform showed a sharp increase in reports concerning Claude AI on Friday afternoon. At around 3:45 PM IST, the platform recorded 2,895 reports against a baseline of two, indicating a significant increase in reported problems.
Claude services affected by the outage
Anthropic's status dashboard shows different levels of disruption across its services. Claude.ai has been marked as experiencing a major outage, while Claude Console (platform.claude.com) and Claude Code are listed under partial outages. Claude Cowork is also reporting degraded performance.
Meanwhile, Claude API continues to be listed as operational on the company's status dashboard. This suggests that the current disruption is not affecting all Claude services uniformly.
Microsoft 365 service incident also affects Claude
Separately, Anthropic has confirmed that a Microsoft 365 service incident is affecting its Microsoft 365 connector and Claude for Outlook. In its November 12 update, the company explicitly attributed the connector-related disruption to a Microsoft 365 service incident.
The issue has been affecting mail, calendar and search tools within the Microsoft 365 connector, with most requests continuing to fail. Anthropic also reported problems with SharePoint and Teams chat during its initial investigation. Claude for Outlook has been affected as well, with mail and calendar actions failing for some users and some unable to open the add-in.
Anthropic first reported elevated errors and slow responses on November 12 at 17:52 UTC. It subsequently identified an issue with an upstream provider and said it was working with the provider as affected servers were being restarted. In its latest update at 22:23 UTC, the company confirmed that the disruption was caused by a Microsoft 365 service incident and directed users to Microsoft's official service status page for further updates.
However, Anthropic has not linked this Microsoft 365 incident to the separate authentication problems affecting Claude.ai, Claude Code and Claude Console on November 13.
