I downloaded the OS X Yosemite combo update from the official apple website! And I wanted to install it onto a separate portion on my Mac. I went to restore this portion with the .dmg image and it said it could not do this? Anyone know how to do this!
MacBook Air 13″, macOS 10.15
The Yosemite Combo Update you downloaded is exactly that an update.
These updates can only be applied if you have an earlier version of Yosemite installed
and running.
What you need to do is download the full installer disk image called InstallMacOSX.dmg.
Follow the instructions below,
If you do have an operating system on your mac and it is functioning then you can download
Yosemite using this method.
Click on the link below,
How to get old versions of macOS – Apple Support
Go to Download macOS and click on OS X Yosemite 10.10
this downloads InstallMacOSX.dmg to your Downloads folder.
The next section can only be done on a mac that is capable of running Yosemite,
a mac that came preinstalled with an OS later than Yosemite will refuse to do the next bit.
When downloaded open to InstallMacOSX.pkg, double-click on
that and an installation window will open, this does not install Yosemite
but converts the InstallMacOSX.pkg to the Install OS X Yosemite.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 Yosemite on, that is for later.)
To start the installation of Yosemite double click on the Install OS X Yosemite.app.
The copy of the install app self deletes after installing Yosemite, so make sure you keep a copy of the InstallMacOSX.dmg
if you need it in future, or you could just make a copy of the Install OS X Yosemite.app prior to installing and moving it to
an external drive for safe keeping. It is also possible to create a bootable USB installer disk using the Install OS X Yosemite.app
in the Applications folder and the createinstallmedia command in the Terminal app.
Read the instructions here,
How to create a bootable installer for macOS – Apple Support
sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Yosemite.app
The Yosemite Combo Update you downloaded is exactly that an update.
These updates can only be applied if you have an earlier version of Yosemite installed
and running.
What you need to do is download the full installer disk image called InstallMacOSX.dmg.
Follow the instructions below,
If you do have an operating system on your mac and it is functioning then you can download
Yosemite using this method.
Click on the link below,
How to get old versions of macOS – Apple Support
Go to Download macOS and click on OS X Yosemite 10.10
this downloads InstallMacOSX.dmg to your Downloads folder.
The next section can only be done on a mac that is capable of running Yosemite,
a mac that came preinstalled with an OS later than Yosemite will refuse to do the next bit.
When downloaded open to InstallMacOSX.pkg, double-click on
that and an installation window will open, this does not install Yosemite
but converts the InstallMacOSX.pkg to the Install OS X Yosemite.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 Yosemite on, that is for later.)
To start the installation of Yosemite double click on the Install OS X Yosemite.app.
The copy of the install app self deletes after installing Yosemite, so make sure you keep a copy of the InstallMacOSX.dmg
if you need it in future, or you could just make a copy of the Install OS X Yosemite.app prior to installing and moving it to
an external drive for safe keeping. It is also possible to create a bootable USB installer disk using the Install OS X Yosemite.app
in the Applications folder and the createinstallmedia command in the Terminal app.
Read the instructions here,
How to create a bootable installer for macOS – Apple Support
sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Yosemite.app
Thank you very helpful!
Download OS X Yosemite on a different partition?