*If you can not install High Sierra by using the High Sierra installer application stored in the High Sierra Recovery partition or from booting to Internet Recovery, then the steps below could be used as an alternative.* 1. Create a bootable USB Mountain Lion installer. The instructions are given in the section titled *“How to Create a USB Flash Drive Mountain Lion Installer from OS X/macOS Recovery”* of [this answer][1]. 2. Follow [this answer][2] starting at step 2. Note: At step 6, substitute http://maclinks.publicvm.com for the link [How to download macOS][3]. [1]: https://apple.stackexchange.com/questions/461234/cannot-install-macos-because-new-account-never-linked-to-macos-will-a-bootable/461242#461242 [2]: https://apple.stackexchange.com/questions/460216/high-sierra-internet-recovery-cannot-contact-server/460246#460246 [3]: https://support.apple.com/en-us/HT211683