| Previous | Next |
| TPM_E_NO_ENDORSEMENT | TPM_E_WRONG_ENTITYTYPE |
TPM_E_INVALID_KEYUSAGE
Read the result in context
TPM_E_INVALID_KEYUSAGE (0x80280024) belongs to TPM 1.2 command processing. The base What Is page already shows the short Windows message; the additional diagnostic value is that this result marks the requested operation conflicts with the usage attributes encoded in the TPM 1.2 key object.
The first producer to identify for this HRESULT is the TPM 1.2 command decoder and state machine. TPM 1.2 is a command/response device with strict binary structures and stateful resources. Windows may present the device response as an HRESULT, but the diagnostic meaning still belongs to the command field, key, session, PCR, NV index or lifecycle check named by the TPM specification.
Fields worth decoding
| Question | Evidence for this HRESULT |
|---|---|
| What exact state was rejected? | the requested operation conflicts with the usage attributes encoded in the TPM 1.2 key object |
| Which layer owns the result? | The TPM 1.2 command decoder and state machine. |
| What must be correlated? | keyUsage, keyFlags, algorithm parameters, command ordinal, requested sign/decrypt/bind/migrate action, and the public portion of the key |
| What is the controlled comparison? | use the same command with a disposable key created for the required usage and compare before altering the original key |
Record the original command or API call before this result retry logic mutates its nonces, handles, buffers or state. Also retain the full HRESULT as 0x80280024; signed decimal logging can hide the result TPM/TBS facility and make searches less precise.
Controlled comparison
- Establish the result baseline with the same device, Windows build, account and TPM generation.
- Perform one narrow experiment: use the same command with a disposable key created for the required usage and compare before altering the original key.
- Compare raw this result inputs and the first response, not only the final application dialog.
- Stop after the first changed the checkpoint; a later error means this boundary was passed even if the whole workflow still fails.
Adjacent failure boundaries
| Result | Different diagnostic question |
|---|---|
TPM_E_WRONG_ENTITYTYPE | The submitted entity type is not allowed — a separate checkpoint when compared with this result. |
TPM_E_NO_ENDORSEMENT | The TPM does not have an Endorsement Key (EK) installed — a separate checkpoint when compared with it. |
TPM_E_INVALID_POSTINIT | The command was received in the wrong sequence relative to TPM_Init and a subsequent TPM_Startup — a separate checkpoint when compared with it. |
The decisive distinction for this HRESULT is that TPM_E_BAD_KEY_PROPERTY rejects unsupported key parameters, while this code rejects what the caller is trying to do with the key. The short platform wording — “The usage of a key is not allowed.” — does not supply that differential diagnosis by itself.
Repair without destroying evidence
The corrective direction is to select or create a key whose declared TPM usage matches the operation; key usage is not safely repaired by changing only application metadata. Do not clear ownership, delete keys or reset PCR-related state merely to see whether the message disappears; those actions can destroy the evidence and protected material while leaving serialization or command-order defects unchanged.
A verified it repair reproduces the original request with the same intended security policy and passes this checkpoint. Replacing it with a broader wrapper status, silently falling back to software keys, or suppressing verification is not proof of success.
Technical references
- TCG: TPM 1.2 Main Specification — source for the checkpoint.
- TCG: TPM 1.2 Part 2 — Structures — source for the checkpoint.
- TCG: TPM 1.2 Part 3 — Commands — source for the checkpoint.
- Microsoft: TPM Base Services portal — source for the checkpoint.
Looking for a different code? Search another status or error code.