900 Official

No Header Information

A required HTTP header is missing from the request.

Likely Causes

Authorization header missing
tin, bhfId, or cmcKey missing from OSCU request headers
Content-Type not set to application/json
A present-but-empty (0-byte) cmcKey device file on the VSCU path — file-exists bootstrap checks pass, but the JAR sends an empty credential (verified live 2026-07-04)

Fix

For OSCU, every request after initialization requires tin, bhfId, and cmcKey in the request headers or body depending on the endpoint. Verify all three are present.

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