Checks if a value exists in the registry.
bExists = ExistsRegistryValue (rcCategory, sKeypath, sValueName)
| Variable | Description | 
|---|---|
| bExists | True if the value exists, false otherwise. Boolean. | 
| rcCategory | The root key for the registry. RegistryCategory. | 
| sKeypath | The path to the registry key. String. | 
| sValueName | The name of the registry value. String. |