What does HRESULT 0x80280028 (TPM_E_BAD_KEY_PROPERTY) mean?

TPM_E_BAD_KEY_PROPERTY

The requested key template has an unsupported property combination

TPM_E_BAD_KEY_PROPERTY (0x80280028) means key creation/loading validation rejected the template itself. Individual fields can look valid while their combination is prohibited by the TPM 1.2 implementation or key type.

Evidence to capture

Capture algorithm ID, key size, usage, auth/migratable flags, exponent/parameters, scheme, and the exact key-template blob. Compare with a known-good template for the same intended role.

Focused correction

Construct a key template using a supported property combination for the target TPM and purpose. Keep the intended cryptographic role fixed while changing only the invalid template fields.

Technical references

• TCG: TPM 1.2 Main Specification.
• TCG: TPM 1.2 Part 2 — Structures.
• TCG: TPM 1.2 Part 3 — Commands.
• Microsoft: TPM Base Services portal.