.NET (Core and Framework)

public static void SetGroupRegInfo(string group, string key, string value)
{
    RegistryKey rkApp = Registry.LocalMachine.CreateSubKey(
                REGISTRY_MICA_GROUPS + "\\" + group,
                RegistryKeyPermissionCheck.ReadWriteSubTree);

    try
    {
        rkApp.SetValue(key, value);
    }
    finally
    {
        rkApp.Close();
    }
}

public static string GetGroupRegInfo(string group, string key)
{
    RegistryKey rkApp = Registry.LocalMachine.OpenSubKey(
                            REGISTRY_MICA_GROUPS + "\\" + group,
                            RegistryKeyPermissionCheck.ReadSubTree,
                            RegistryRights.QueryValues);

    if (rkApp == null)
        return null;

    try
    {
        return (string)rkApp.GetValue(key);
    }
    finally
    {
        rkApp.Close();
    }
}