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# WKError

Possible error values that WebKit APIs can return.

```
struct WKError
```

## Topics

### Getting the Error Codes

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

An error that indicates an unknown issue occurred.

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

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

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

An error that indicates the web view was invalidated.

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

An error that indicates a JavaScript exception occurred.

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

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

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

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

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

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

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

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

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

An error that indicates the rule list version is outdated and cannot be read.

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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


---

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