# Invalid Key Type
source: https://developer.mastercard.com/mastercard-developers-api/documentation/errors/invalid-key/index.md

Your request contains an invalid credential type (SIGNING) for this service.

### Solution {#solution}

Ensure you are using a credential that your service/API supports.

### API Error Response {#api-error-response}

**HTTP code 400**

```JSON

{
  "Errors": {
    "Error": [
      {
        "Source": "DEVELOPERS_PLATFORM",
        "ReasonCode": "INVALID_KEY_TYPE",
        "Description": "Invalid credential type",
        "Details": "Invalid credential type (SIGNING) for this request",
        "Recoverable": false
      }
    ]
  }
}
```

[Back to Errors List](https://developer.mastercard.com/mastercard-developers-api/documentation/code-and-formats/index.md#list-of-common-api-errors)​​