Hi
I have an iMac mid 2011 which I have been running on an external SSD as the HD.
I now want to restore the iMac and run it off the original SATA internal HD, which I had been using as a drive for files. It's now formatted as a Mac OS Extended (Journaled).
How can I reinstall OSX Sierra back onto the old HD?
Any help much appreciated!
iMac 21.5″, macOS 10.13
If you simply want to take all the data from the SSD which is running Sierra and put it on the
internal HD then use Migration Assistant.
When booted up in the SSD open Applications/ Utilities and click on Migration Assistant.
It will ask you if you want to migrate your date to another mac, treat the internal disk as the other mac.
The next window should show you the available disks to migrate to.
Follow the prompts.
If on the other hand you want to download the macOS Sierra installer app then
you can get it from here.
How to upgrade to macOS Sierra - Apple Support
Go to Section 4 and click on Download macOS Sierra.
This downloads InstallOS.dmg to your Downloads folder.
The next section can only be done on a mac that is capable of running Sierra,
a mac that came preinstalled with an OS later than Sierra will refuse to do the next bit.
When downloaded open to get InstallOS.pkg, double-click on
that and an installation window will open, read and follow the prompts,
this does not install Sierra but uses the InstallOS.pkg to create the
Install macOS Sierra.app which you will find in your Applications folder.
(If the installation window asks which disk you want to install to, you must pick
the disk that you are booted to at the time. Not any internal or external disk that
you want to eventually install Sierra on, that is for later.)
To start the installation of Sierra double click on the Install macOS Sierra.app.
The installation process will startup, at one stage you will be asked to choose
the disk you want to install macOS Sierra to, this is where you select the macs internal HD.
This will install a fresh copy of Sierra, you can then use Migration Assistant to migrate
any apps or personal data to the internal drive, or you can do it all manually.
The copy of the install app self deletes after installing Sierra, so make sure you keep a copy of the InstallOS.dmg
if you need it in future, or you could just make a copy of the Install OS X Sierra.app prior to installing and moving
it to an external drive for safe keeping.
If you simply want to take all the data from the SSD which is running Sierra and put it on the
internal HD then use Migration Assistant.
When booted up in the SSD open Applications/ Utilities and click on Migration Assistant.
It will ask you if you want to migrate your date to another mac, treat the internal disk as the other mac.
The next window should show you the available disks to migrate to.
Follow the prompts.
If on the other hand you want to download the macOS Sierra installer app then
you can get it from here.
How to upgrade to macOS Sierra - Apple Support
Go to Section 4 and click on Download macOS Sierra.
This downloads InstallOS.dmg to your Downloads folder.
The next section can only be done on a mac that is capable of running Sierra,
a mac that came preinstalled with an OS later than Sierra will refuse to do the next bit.
When downloaded open to get InstallOS.pkg, double-click on
that and an installation window will open, read and follow the prompts,
this does not install Sierra but uses the InstallOS.pkg to create the
Install macOS Sierra.app which you will find in your Applications folder.
(If the installation window asks which disk you want to install to, you must pick
the disk that you are booted to at the time. Not any internal or external disk that
you want to eventually install Sierra on, that is for later.)
To start the installation of Sierra double click on the Install macOS Sierra.app.
The installation process will startup, at one stage you will be asked to choose
the disk you want to install macOS Sierra to, this is where you select the macs internal HD.
This will install a fresh copy of Sierra, you can then use Migration Assistant to migrate
any apps or personal data to the internal drive, or you can do it all manually.
The copy of the install app self deletes after installing Sierra, so make sure you keep a copy of the InstallOS.dmg
if you need it in future, or you could just make a copy of the Install OS X Sierra.app prior to installing and moving
it to an external drive for safe keeping.
Thank you, that's really helpful!
Restoring iMac to Sierra
