InvalidAuthenticationInfo
Azure Storage returns `InvalidAuthenticationInfo` (401) when request authentication details are missing or invalid and the service cannot authenticate the caller.
Last reviewed: February 4, 2026|Editorial standard: source-backed technical guidance
What Does Invalid Authentication Info Mean?
Storage rejects the request at the authentication layer, so data operations fail immediately until the caller sends valid auth metadata.
Common Causes
- -Authorization header is missing or malformed for the selected authentication method.
- -Bearer token, shared key signature, or SAS data is invalid for the target request.
- -Client and service disagree on signed request components after proxy/header mutation.
- -Caller ignores
WWW-Authenticatechallenge details required for proper auth.
How to Fix Invalid Authentication Info
- 1Inspect
WWW-Authenticateheader in the 401 response and correct auth flow accordingly. - 2Validate Authorization header construction, including scheme and signature/token format.
- 3Regenerate token, SAS, or signed headers with fresh credentials and replay request.
- 4Ensure intermediaries do not strip or rewrite signed authentication headers.
Step-by-Step Diagnosis for Invalid Authentication Info
- 1Capture full request/response pair including Authorization and
WWW-Authenticateheaders. - 2Verify authentication mode (OAuth, Shared Key, SAS) matches the endpoint and SDK configuration.
- 3Recompute signature or token claims against the exact canonical request that was sent.
- 4Replay with a known-good minimal request from Azure CLI/SDK to isolate client implementation drift.
Authorization Header Integrity Checks
- -Validate final outbound Authorization header after all middleware layers (example: API gateway strips signed headers before reaching Storage endpoint).
- -Confirm auth scheme matches credential type (example: Shared Key string sent while client is configured for Bearer token flow).
Challenge and Signing Context Analysis
- -Parse
WWW-Authenticatechallenge details and align client response (example: tenant/resource mismatch in bearer challenge is ignored by caller). - -Audit canonicalized signed elements for Shared Key requests (example: header ordering differs between signer and transmitted request).
How to Verify the Fix
- -Replay the same Storage operation and confirm
InvalidAuthenticationInfono longer returns. - -Validate successful auth across all environments and deployment slots using the same auth mode.
- -Check monitoring for elimination of repeated 401 signatures on the affected endpoint.
How to Prevent Recurrence
- -Standardize one authentication library/path per service to avoid ad hoc header construction.
- -Add preflight validation that inspects final outbound Authorization metadata in integration tests.
- -Monitor Storage 401 patterns and alert when
WWW-Authenticatechallenges spike unexpectedly.
Pro Tip
- -store redacted canonical request components for signed calls so signature mismatches can be reproduced without exposing secrets.
Decision Support
Compare Guide
HTTP 400 vs 422: Bad Request vs Unprocessable Content
Fix API payload issues faster by using 400 for malformed syntax and 422 for semantic validation failures, so clients correct format before business rules.
Playbook
CORS Error Fix Playbook (Preflight / Origin / Credentials)
Use this playbook to separate browser-enforced cross-origin policy failures from server-side CORS header and route defects and apply strict origin and credential controls safely.
Playbook
Validation Failure Playbook (400 / 422 / INVALID_ARGUMENT)
Use this playbook to separate malformed-request failures from semantic validation failures, then fix request contracts without broad server-side bypasses.
Official References
Provider Context
This guidance is specific to Azure services. Always validate implementation details against official provider documentation before deploying to production.