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# WKError.Code

Possible error values that WebKit APIs can return.

```
enum Code
```

## Topics

### Errors

[`WKError.Code.unknown`](/documentation/WebKit/WKError/Code/unknown)

An error that indicates an unknown issue occurred.

[`WKError.Code.webContentProcessTerminated`](/documentation/WebKit/WKError/Code/webContentProcessTerminated)

An error that indicates the web process that contains the content is no longer running.

[`WKError.Code.webViewInvalidated`](/documentation/WebKit/WKError/Code/webViewInvalidated)

An error that indicates the web view was invalidated.

[`WKError.Code.javaScriptExceptionOccurred`](/documentation/WebKit/WKError/Code/javaScriptExceptionOccurred)

An error that indicates a JavaScript exception occurred.

[`WKError.Code.javaScriptResultTypeIsUnsupported`](/documentation/WebKit/WKError/Code/javaScriptResultTypeIsUnsupported)

An error that indicates the result of JavaScript execution could not be returned.

[`WKError.Code.contentRuleListStoreCompileFailed`](/documentation/WebKit/WKError/Code/contentRuleListStoreCompileFailed)

An error that indicates the compilation of a rule list failed.

[`WKError.Code.contentRuleListStoreLookUpFailed`](/documentation/WebKit/WKError/Code/contentRuleListStoreLookUpFailed)

An error that indicates a content rule list data store didn’t find a rule list with the specified identifier.

[`WKError.Code.contentRuleListStoreRemoveFailed`](/documentation/WebKit/WKError/Code/contentRuleListStoreRemoveFailed)

An error that indicates a failure to remove a content rule list from the rule list data store object.

[`WKError.Code.contentRuleListStoreVersionMismatch`](/documentation/WebKit/WKError/Code/contentRuleListStoreVersionMismatch)

An error that indicates the rule list version is outdated and cannot be read.

[`WKError.Code.attributedStringContentFailedToLoad`](/documentation/WebKit/WKError/Code/attributedStringContentFailedToLoad)

An error that indicates the failure to navigate to web content from an attributed string.

[`WKError.Code.attributedStringContentLoadTimedOut`](/documentation/WebKit/WKError/Code/attributedStringContentLoadTimedOut)

An error that indicates a timeout occurred while trying to load web content from an attributed string.

[`WKError.Code.javaScriptInvalidFrameTarget`](/documentation/WebKit/WKError/Code/javaScriptInvalidFrameTarget)

An error that indicates your content referenced an invalid web frame.

[`WKError.Code.navigationAppBoundDomain`](/documentation/WebKit/WKError/Code/navigationAppBoundDomain)

An error that indicates navigation failed due to an app-bound domain restriction.

[`WKError.Code.javaScriptAppBoundDomain`](/documentation/WebKit/WKError/Code/javaScriptAppBoundDomain)

An error that indicates JavaScript execution failed due to an app-bound domain restriction.

[`WKError.Code.credentialNotFound`](/documentation/WebKit/WKError/Code/credentialNotFound)

An error that indicates the system could not find a passkey during an export.

[`WKError.Code.duplicateCredential`](/documentation/WebKit/WKError/Code/duplicateCredential)

An error that indicates the system found a duplicate passkey during an import.

[`WKError.Code.malformedCredential`](/documentation/WebKit/WKError/Code/malformedCredential)

An error that indicates the system could not parse passkey data during an import.


---

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