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# serverUnavailable

An error that indicates a failed attempt to contact the App Attest service during an attestation.

```
static var serverUnavailable: DCError.Code { get }
```

## Discussion

You receive this error when you call [`attestKey(_:clientDataHash:completionHandler:)`](/documentation/DeviceCheck/DCAppAttestService/attestKey(_:clientDataHash:completionHandler:))
and the framework isn’t able to complete the attestation. If you receive this error,
try the attestation again later using the same key and the same value for the `clientDataHash`
parameter. Retrying with the same inputs helps to preserve the risk metric for a given device.

---

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