internal static extern int GetLablesByAppId(LabelCallback callback, string appId, IntPtr userData);
internal static extern int GetAccountProviderLabels(IntPtr handle, LabelCallback callback, IntPtr userData);
internal static extern int GetLablesByAppId(LabelCallback callback, string appId, IntPtr userData);
internal static extern int GetAccountProviderLabels(IntPtr handle, LabelCallback callback, IntPtr userData);