# Claude Login Errors: Check the Outage Before Resetting Your Setup

November 13 authentication failures and a separate Microsoft 365 connector incident require different checks, even when both appear inside Claude.

By Paras Madan | 2026-11-13


Claude authentication failures on November 13 were a confirmed service incident, not automatically a broken local installation. Anthropic posted a fix at 11:05 UTC and moved the incident to monitoring. A separate Microsoft 365 connector incident remained open, so restored login did not establish that every connected workflow was working.

This status snapshot uses the latest incident updates checked for the November 13, 11:30 UTC publishing run. Consult the linked incident records for subsequent changes. The troubleshooting steps below are a proposed diagnostic workflow, not a report of testing an affected account.

## Separate login failure from connector failure

Anthropic's [authentication incident](https://status.claude.com/incidents/nn11wk485zfn) began investigating at 09:58 UTC. Its listed affected products include claude.ai, Claude Console, Claude Code and Claude Cowork. At 11:05 UTC, Anthropic said a fix had been deployed and recovery was being monitored. Monitoring is not the same as a resolved incident or proof that every user has recovered.

The [Microsoft 365 connector incident](https://status.claude.com/incidents/sqn3fg1l96dl) is separate. Its latest update checked here, at 22:23 UTC on November 12, attributes the problem to a Microsoft 365 service incident. Anthropic says mail, calendar and search tools were failing for most requests, with Claude for Outlook also affected.

That distinction prevents a costly detour. If you can open Claude and complete an ordinary chat but Outlook-related work fails, repeatedly reinstalling Claude Code is unlikely to address the reported upstream issue. Record which product and operation failed before changing credentials or configuration.

## Use the error, not just the word “Claude”

A browser login problem and an API response come from different access paths. Anthropic's [API error reference](https://platform.claude.com/docs/en/api/errors) distinguishes several cases:

| Error | What it tells you to investigate |
| --- | --- |
| 401 authentication error | API credentials or the specific authentication message |
| 403 permission error | Permission to use the requested resource |
| 429 rate-limit error | Rate or spending limits, including the detailed error and any retry guidance |
| 500 API error | A server-side error; use exponential backoff |
| 529 overloaded error | Temporary API overload |

Do not apply that table mechanically to a website's login screen. Preserve the exact message and access method. In particular, a 429 can reflect a spending cap rather than a temporary traffic limit, and some 401 messages describe an organization's browser-access restriction rather than a bad key. The detailed response matters more than the number alone.

For a team incident, collect a small evidence set: UTC time, product, authentication method, operation, error text and request identifier where available. Exclude tokens and private content. This is enough to distinguish several classes of failure without circulating a full conversation or credential-bearing log.

## Diagnose locally only after checking the service

For problems that continue after service recovery, the [Claude Code troubleshooting guide](https://code.claude.com/docs/en/troubleshooting) routes login loops, OAuth errors and organization restrictions to its installation-and-login guidance. Settings and MCP issues have a separate configuration path.

Inside Claude Code, `/doctor` checks the installation, settings, extensions and context usage. If Claude cannot start, `claude doctor` is the shell alternative. Review any proposed fix before confirming it. `/mcp` checks MCP server status; it should not be treated as a universal repair for every connector in every Claude product.

My recommendation is to change one thing at a time and preserve the original symptom. Simultaneously reinstalling the client, resetting authentication and changing proxy settings makes it harder to determine whether the provider recovered or a local change helped. During an acknowledged outage, an unexplained local “fix” is weak evidence.

If an interrupted workflow could have sent a message or changed a record, check the destination before retrying the action. A missing response does not establish that nothing happened. Keep read-only diagnosis separate from repeating work with side effects.

The useful outcome is identifying the failing layer without damaging a working setup. When the provider has confirmed an incident, patience plus a precise error record can be better engineering than another round of resets.

I'm Paras. I work at the intersection of AI, engineering and distribution.

I help AI teams write practical troubleshooting guides and technical explanations that make their products easier to understand.

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