Since macOS Sierra 10.12.4 Apple has provided three different macOS Recovery options. These are described below: - <kbd>command</kbd><kbd>R</kbd> to reinstall the **latest macOS that was installed** on your Mac, without upgrading to a later version - <kbd>option</kbd><kbd>command</kbd><kbd>R</kbd> to upgrade to the **latest macOS that is compatible** with your Mac - <kbd>shift</kbd><kbd>option</kbd><kbd>command</kbd><kbd>R</kbd> to reinstall the **macOS that came with your Mac**, or the version *closest* to it that is still available<sup>1</sup> So, the best options if you're wanting to install macOS High Sierra from Recovery mode is to use the: - <kbd>command</kbd><kbd>R</kbd> shortcut (since that's the last version of macOS you had installed), or the - <kbd>option</kbd><kbd>command</kbd><kbd>R</kbd> shortcut as that's the one for installing the latest macOS compatible with your hardware.