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# netService(_:didNotResolve:)

Informs the delegate that an error occurred during resolution of a given service.

```
optional func netService(_ sender: NetService, didNotResolve errorDict: [String : NSNumber])
```

## Parameters

`sender`

The service that did not resolve.

`errorDict`

A dictionary containing information about the problem. The dictionary contains the keys [`errorCode`](/documentation/Foundation/NetService/errorCode-swift.type.property) and [`errorDomain`](/documentation/Foundation/NetService/errorDomain).

## Discussion

Clients may try to resolve again upon receiving this error. For example, a DNS rotary may yield different IP addresses on different resolution requests. A common error condition is that no addresses were resolved during the timeout period specified in [`resolve(withTimeout:)`](/documentation/Foundation/NetService/resolve(withTimeout:)).

---

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