InvalidAddressingHeader
AWS InvalidAddressingHeader means the request is missing or using an invalid addressing-role header; in S3 this appears with the message "You must specify the Anonymous role" (HTTP status listed as N/A).
Last reviewed: February 6, 2026|Editorial standard: source-backed technical guidance
What Does Invalid Addressing Header Mean?
The call is rejected during request qualification, so the operation never reaches object processing until role/addressing expectations are met.
Common Causes
- -Request omits a role/addressing value required by the target S3 request path.
- -Client sends authenticated addressing context where the endpoint/workflow expects Anonymous-role behavior.
- -Legacy request templates carry stale addressing-role header assumptions.
- -Proxy or gateway rewrites role-related headers before the request reaches S3.
How to Fix Invalid Addressing Header
- 1Review the exact S3 operation contract and identify required role/addressing semantics.
- 2Apply the required Anonymous-role addressing behavior for that request path.
- 3Remove conflicting auth/addressing headers that violate the target endpoint expectations.
- 4Retest using a minimal SDK/CLI request and then reintroduce custom middleware incrementally.
Step-by-Step Diagnosis for Invalid Addressing Header
- 1Capture full request URL, headers, and AWS request identifiers from the failed call.
- 2Determine whether the endpoint/workflow expects Anonymous-role semantics for addressing.
- 3Diff failing traffic against a known-good request for the same operation path.
- 4Inspect proxy, service mesh, and middleware layers for role/addressing header rewrites.
Anonymous Role Requirement Checks
- -Inspect addressing-role fields and verify required Anonymous-role semantics are present (example: custom client leaves role unset on a path that requires Anonymous role declaration).
- -Audit endpoint routing rules that switch between anonymous and authenticated request modes (example: public-content route accidentally inherits authenticated role headers).
Header Rewrite and Legacy Template Audit
- -Trace role/addressing headers before and after middleware layers (example: gateway policy strips role-related header set by upstream signer).
- -Compare legacy request templates with current SDK defaults (example: old hand-built template sends deprecated addressing-role pattern that modern S3 rejects).
How to Verify the Fix
- -Re-run request and confirm InvalidAddressingHeader is cleared.
- -Validate the request now uses the required role/addressing semantics end to end.
- -Confirm the same operation succeeds consistently across all runtime environments.
How to Prevent Recurrence
- -Centralize role/addressing header generation in one shared request builder.
- -Add integration tests for anonymous-mode and authenticated-mode S3 routes separately.
- -Block unreviewed header rewrite policies on S3 traffic paths.
Pro Tip
- -include an explicit endpoint-mode flag in your transport abstraction and assert allowed header sets per mode before dispatch.
Decision Support
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Playbook
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Official References
Provider Context
This guidance is specific to AWS services. Always validate implementation details against official provider documentation before deploying to production.