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  "title" : "AccessorySecuritySession.Error"
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# AccessorySecuritySession.Error

An error that occurs during accessory security-session operations.

```
enum Error
```

## Overview

The framework throws errors of this type when security-session operations fail. Use the error cases to determine the specific cause and handle it appropriately in your accessory transport-security extension.

## Topics

### Interpreting the error cause

[`case invalidated`](/documentation/AccessoryTransportExtension/AccessorySecuritySession/Error/invalidated)

Session was invalidated.

[`case unknown`](/documentation/AccessoryTransportExtension/AccessorySecuritySession/Error/unknown)

Underlying failure with an unknown cause.

[`case unsupported`](/documentation/AccessoryTransportExtension/AccessorySecuritySession/Error/unsupported)

Unsupported value, operation, etc.

### Accessing error details

[`var description: String`](/documentation/AccessoryTransportExtension/AccessorySecuritySession/Error/description)

A string that describes the error.

## Relationships

### Conforms To

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

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

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

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

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

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

---

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