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# OSSystemExtensionError

An error that describes a failed extension manager request.

```
struct OSSystemExtensionError
```

## Topics

### Inspecting Error Properties

[`errorDomain`](/documentation/SystemExtensions/OSSystemExtensionError/errorDomain)

The domain of SystemExtension errors.

### Error Codes

[`OSSystemExtensionError.Code`](/documentation/SystemExtensions/OSSystemExtensionError/Code)

Error codes for system extensions.

[`unknown`](/documentation/SystemExtensions/OSSystemExtensionError/unknown)

An error code that indicates an unknown error occurred.

[`missingEntitlement`](/documentation/SystemExtensions/OSSystemExtensionError/missingEntitlement)

An error code that indicates the system extension lacks a required entitlement.

[`unsupportedParentBundleLocation`](/documentation/SystemExtensions/OSSystemExtensionError/unsupportedParentBundleLocation)

An error code that indicates the extension’s parent app isn’t in a valid location for activation.

[`extensionNotFound`](/documentation/SystemExtensions/OSSystemExtensionError/extensionNotFound)

An error code that indicates the manager can’t find the system extension.

[`extensionMissingIdentifier`](/documentation/SystemExtensions/OSSystemExtensionError/extensionMissingIdentifier)

An error code that indicates the extension identifier is missing.

[`duplicateExtensionIdentifer`](/documentation/SystemExtensions/OSSystemExtensionError/duplicateExtensionIdentifer)

An error code that indicates the extension identifier duplicates an existing identifier.

[`unknownExtensionCategory`](/documentation/SystemExtensions/OSSystemExtensionError/unknownExtensionCategory)

An error code that indicates the extension manager can’t recognize the extension’s category identifier.

[`codeSignatureInvalid`](/documentation/SystemExtensions/OSSystemExtensionError/codeSignatureInvalid)

An error code that indicates the extension’s signature is invalid.

[`validationFailed`](/documentation/SystemExtensions/OSSystemExtensionError/validationFailed)

An error code that indicates the manager can’t validate the extension.

[`forbiddenBySystemPolicy`](/documentation/SystemExtensions/OSSystemExtensionError/forbiddenBySystemPolicy)

An error code that indicates the system policy prohibits activating the system extension.

[`requestCanceled`](/documentation/SystemExtensions/OSSystemExtensionError/requestCanceled)

An error code that indicates the system extension manager request was canceled.

[`requestSuperseded`](/documentation/SystemExtensions/OSSystemExtensionError/requestSuperseded)

An error code that indicates the system extension request failed because the system already has a pending request for the same identifier.

[`authorizationRequired`](/documentation/SystemExtensions/OSSystemExtensionError/authorizationRequired)

An error code that indicates the system was unable to obtain the proper authorization.

### Comparing Error Instances


---

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