MacOS – Upgrade then restore, or the other way around

macosmojaverestoretime-machineupgrade

I'm in a situation where I simply cannot upgrade my Mac – the installer says that my disk cannot be used as a startup disk. This probably has to do with me installing dual-boot partitions, but I'm not sure.

I've decided to just wipe the disk and restore from backup. In the process, I'd like to upgrade to the most recent Mac OS version as well.

My question is simply: what is the most reasonable approach – upgrade the OS using a USB stick and then read back from the backup disk, or the other way around: restore from the disk, then run the upgrade?

Thanks.

Best Answer

Apple's Migration Assistant does a great job at importing data from previous installations or backups. Therefore, I suggest you save yourself some time and do a clean install of the version of macOS you want to finally use and then use Migration Assistant to recover your Apps, profiles, etc.

As suggested by @SteveChambers:

back up
create a bootable USB installer or use internet recovery
reformat the drive
install macOS,
restore from backup using Migration Assistant

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ICloud restore issue on iPhone 4S

I've encountered a similar error on my iPhone 4S while restoring an iCloud backup. I fixed it by simply updating the firmware/iOS version to the latest version available from Apple. Latest iOS 7.1.2 was out at that time but I was running outdated iOS 7.0.4. Once the phone restored with the latest iOS version, I was able to restore from iCloud. So update your iOS if you're using an older iOS version and try again.

MacOS – Attempting to revert to Mac OS X Mavericks, now can’t get out of OS X Utilities!

Restart your Mac to Recovery Mode by pressing cmd R at startup
Launch Terminal from the menubar Utilities->Terminal

Enter the following command at the Terminal prompt:

defaults write com.apple.DiskUtility DUDebugMenuEnabled 1

Press enter
Quit Terminal
Start Disk Utility and enable Show every Partition in the Debug menu
After a few seconds all partitions should be visible
Activate the partition Macintosh HD if it's present and greyed out.
Erasing/formating of Macintosh HD should be possible now.

If this doesn't work quit Disk Utility and according to this site

Start Terminal and enter following command at the Terminal prompt:
```
diskutil cs list
```
This will give you a list of the CoreStorage volumes on your system. Your old FileVault 2-encrypted drive should be the only one listed.
Copy the Logical Volume Group (LVG) alphanumeric UUID of your CoreStorage volume. The LVG should be the first UUID listed and it’s the one you want to delete.
Next, run the following command:
```
diskutil cs delete lvgUUID #replace lvgUUID here by the UUID you found above
```
This will delete your CoreStorage volume and reformat it as an unencrypted HFS+ volume.

If it's still impossible to erase Macintosh HD or if it's not present consider the Internet Recovery Mode or a USB Recovery drive and format the whole internal drive.

Restart to Internet Recovery Mode by pressing alt cmd R at startup.
The prerequisites are the latest firmware update installed, either ethernet or WLAN (WPA/WPA2) and a router with DHCP activated.
On a 50 Mbps-line it takes about 4 min (presenting a small animated globe) to boot to the recovery netboot image which is loaded from an Apple/Akamai server.
In the opening window choose Disk Utility and format/partition the internal drive. Choose Mac OS Extended (Journaled) and GUID partition table (available with the Options... button). Quit Disk Utility.
Plug in your Time Machine backup drive.
Start Time Machine and recover your old system

Best Answer

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ICloud restore issue on iPhone 4S

MacOS – Attempting to revert to Mac OS X Mavericks, now can’t get out of OS X Utilities!

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