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# CardSession.Error

An error type that indicates problems with a card session.

```
enum Error
```

## Topics

### Card session errors

[`case invalidated`](/documentation/CoreNFC/CardSession/Error/invalidated)

The system invalidated the card session.

[`case userInvalidated`](/documentation/CoreNFC/CardSession/Error/userInvalidated)

The person using the app invalidated the card session.

[`case maxSessionDurationReached`](/documentation/CoreNFC/CardSession/Error/maxSessionDurationReached)

The session is no longer valid because it reached its maximum duration.

[`case transmissionError`](/documentation/CoreNFC/CardSession/Error/transmissionError)

The card session experienced a general error transmitting data.

[`case systemNotAvailable`](/documentation/CoreNFC/CardSession/Error/systemNotAvailable)

A system resource is currently unavailable.

[`case accessNotAccepted`](/documentation/CoreNFC/CardSession/Error/accessNotAccepted)

The person using the app hasn’t yet accepted or declined your app’s request to use the NFC card emulation service.

[`case systemEligibilityFailed`](/documentation/CoreNFC/CardSession/Error/systemEligibilityFailed)

The current system setting or hardware configuation isn’t eligible to use the NFC card emulation service.

[`case emulationStopped`](/documentation/CoreNFC/CardSession/Error/emulationStopped)

The card emulation stopped.

[`case radioDisabled`](/documentation/CoreNFC/CardSession/Error/radioDisabled)

The card session failed because the NFC radio is disabled.

## Relationships

### Conforms To

[`Equatable`](/documentation/Swift/Equatable)

[`Hashable`](/documentation/Swift/Hashable)

[`Error`](/documentation/Swift/Error)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

[`Sendable`](/documentation/Swift/Sendable)

---

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