Writes string data to a value in the registry.
The lpszSubSection parameter is not an absolute path for a registry entry. It is a relative path that is appended to the end of the default registry key for your application. To get or set the default registry key, use the methods CWinAppEx::GetRegistryBase and CWinAppEx::SetRegistryBase, respectively.
If the value specified by lpszEntry does not exist under lpszSubSection, this method will create it.