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# RegisterService

Starts the registration process for the service and performs any additional matching.

```
virtual kern_return_t RegisterService();
```

## Return Value

[`kIOReturnSuccess`](/documentation/DriverKit/kIOReturnSuccess) on success, or another value if an error occurs. For a list of error codes, see [Error Codes](/documentation/DriverKit/error-codes).

## Discussion

After setting up your service in your custom [`Start`](/documentation/DriverKit/IOService/Start) method, call this method to let the system know your service is running.

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