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# AAError

Values that describe errors the AccessoryAccess framework returns.

```
struct AAError
```

## Topics

### Errors

[`static var accessoryListenerAlreadyRegistered: AAError.Code`](/documentation/AccessoryAccess/AAError/accessoryListenerAlreadyRegistered)

An error that indicates the accessory listener is already registered, and therefore the app can’t re-register it.

[`static var accessoryNotAccessible: AAError.Code`](/documentation/AccessoryAccess/AAError/accessoryNotAccessible)

An error that indicates the USB accessory isn’t accessible.

[`static var internalError: AAError.Code`](/documentation/AccessoryAccess/AAError/internalError)

An error that represents an internal error.

[`static var invalidAccessoryState: AAError.Code`](/documentation/AccessoryAccess/AAError/invalidAccessoryState)

An error that indicates the accessory isn’t in the correct state for the current operation.

[`enum Code`](/documentation/AccessoryAccess/AAError/Code)

Values that represent error codes that the AccessoryAccess framework returns.

### Type properties

[`static var errorDomain: String`](/documentation/AccessoryAccess/AAError/errorDomain)

A value that represents the Accessory Access framework’s error domain.

## Relationships

### Conforms To

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

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

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

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

[`CustomNSError`](/documentation/Foundation/CustomNSError)

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

---

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