wenchangmobile Said:
"How to Download macOS Mojave from Apple officially?: Respectful, Recently I updated my Macintosh to macOS Big Sur, but I want to get back to the macOS Mojave, on which I used to work well, but I find it is no longer available on Apple Store! So how can I download it from Apple officially? Please let me know! Many thanks in advance!"
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Seems this all comes down to Backups:
Restore from a Backup:
Do you have a Time Machine Backup of your Mac that you created prior to upgrading to Big Sur? If so, restore from it. If not, then take this as a learning experience, knowing to always create a Time Machine backup of your Mac prior to making any major change to is (i.e. macOS upgrade), so that you can have something to restore your Mac from, should anything go wrong with the upgrade. Important: Be certain to create a backup, prior to any restoration, from here on out.
If you don’t Create One:
If you never created one, then you’d have to take this as a learning experience, and know to always create a backup.
What Else to Try:
If restoring from a back up not an option, them perform the following.
Three Steps:
1. Create a Backup.
Back up your Mac, prior to all of this. That way you can have something to restore you Mac from, should anything go wrong afterwards. All, you;d use this backup for step three shown below. Use this Link:
2. Install Mojave
Create and use a Mojave USB Installer. Go Here: How to Create a Bootable Installer for macOS - Apple Support
3. Import from Backup:
Use Migration Assistant to retrieve this data. Go Here: Restore Items Backed up with Time Machine on Mac - Apple Support