Azure OpenAI (Microsoft Foundry) error
Azure OpenAI 401 Unauthorized: what it means and how to fix it
401 UnauthorizedRetry? Not statedLast verified 1 documented fix1 source
What it means
Authentication failed for the Azure OpenAI endpoint.
Causes
- Invalid API key
- Expired or misconfigured Microsoft Entra token
- Wrong token scope or audience
- Missing RBAC role assignment
How to fix it
- Fix 1.
Verify your API key or token. For Microsoft Entra ID authentication, use the https://ai.azure.com/.default scope for Azure OpenAI endpoints.
More Azure OpenAI errors
All 15 Azure OpenAI errors400 Bad RequestRetry? Not stated400 content_filterRetry? Not stated200 finish_reason: content_filterRetry? Not stated200 content_filter_error (The contents are not filtered)Retry? Not stated403 Forbidden (network access denied)Retry? Not stated403 Forbidden (resource has been temporarily blocked)Retry? Not stated404 Not FoundRetry? Not stated429 Too Many Requests (Rate limit is exceeded)Retry? Yes
HTTP 401 at other providers
Compare 401 across providers401 authentication_errorRetry? Not statedAnthropic API401 UnauthorizedRetry? Not statedCohere API401 - Authentication FailsRetry? Not statedDeepSeek API401 authenticationRetry? NoGemini API401 UnauthorizedRetry? Not statedGroq API401 UnauthorizedRetry? Not statedMistral API401 Invalid AuthenticationRetry? Not statedOpenAI API401 Incorrect API key providedRetry? Not statedOpenAI API401 You must be a member of an organization to use the APIRetry? Not statedOpenAI API401 IP not authorizedRetry? Not statedOpenAI API401 authenticationRetry? Not statedOpenRouter401 UNAUTHENTICATEDRetry? NoVertex AI
FAQ
What does the Azure OpenAI error "401 Unauthorized" mean?
Authentication failed for the Azure OpenAI endpoint.
How do I fix Azure OpenAI "401 Unauthorized"?
Verify your API key or token. For Microsoft Entra ID authentication, use the https://ai.azure.com/.default scope for Azure OpenAI endpoints.
Should I retry Azure OpenAI "401 Unauthorized"?
Not stated. The official docs do not say whether this error is retryable.
Which other AI APIs return HTTP 401?
Per their official error docs: Anthropic API (401 authentication_error), Cohere API (401 Unauthorized), DeepSeek API (401 - Authentication Fails), Gemini API (401 authentication), Groq API (401 Unauthorized), Mistral API (401 Unauthorized), OpenAI API (401 Invalid Authentication; 401 Incorrect API key provided; 401 You must be a member of an organization to use the API; 401 IP not authorized), OpenRouter (401 authentication), Vertex AI (401 UNAUTHENTICATED), xAI API (401 Unauthorized).
Sources
Last verified against 1 source: Azure OpenAI's official docs and official SDK repositories.
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