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Reinstall Mojave

Recently installed Big Sur on my 2014 MBP but doesn't play well with some of my apps. Tried to reinstall Mojave but downloader would not install stating that I have the most recent OS. Can't use Time Machine as this is on an external drive which won't open in Big Sur. Anybody know a workaround?

MacBook Pro 13″, macOS 11.6

Posted on Sep 23, 2021 7:30 PM

Reply
Question marked as Top-ranking reply

Posted on Sep 23, 2021 11:46 PM

Before you upgrade to a new OS like macOS Big Sur it is vital you check that any apps that you use with your mac will

continue to work with the new OS. This is especially true because from the introduction of macOS Catalina two

years ago new mac OS's no longer run 32bit apps, and this will continue in future macOS's.

Before upgrading it would have been helpful for you to download and run this free app, https://www.stclairsoft.com/Go64/

This will list all your apps that are 32bit or have 32bit elements, and you can contact the apps developers to see if

they are providing 64 bit updates or alternatives. The same also applies for any printers/ scanners or other hardware you use

with you mac. You can still run the app now, and then check for updates.


Unfortunately when you are on macOS Big Sur it will not let you download older macOS full installers like macOS Mojave.


Can you source another mac that is running an older OS which is capable of downloading the macOS Mojave installer.

On that mac,

Open Safari and click on this link, 

How to get old versions of macOS – Apple Support

Go to the Download OS section and click on macOS Mojave.

This will redirect you to the App Store Mojave download page,

it should say Get or Download.

Once it has completed downloading.

Make a bootable USB installer using these instructions,

How to create a bootable installer for macOS – Apple Support (UK)


Now make a full back up of your mac.


Insert the bootable USB directly to your mac.


Restart your mac while pressing and holding down the option/ alt key.

In about two minutes you will see the Boot Manager, select the USB and

press Return. The mac will now boot to the USB.

From the Utilities panel select Disk Utility and press Continue.

Click View in the menubar and select Show All Devices.

Highlight the Disk (Apple HDD..... or similar) not any of the indented Volumes.

Click Erase.

Give the Disk a name.

Format: APFS.

Scheme: GUID Partition Map.

Click Erase.

When Done quit Disk Utility.


Click on Install OS and press Continue.

The installation procedure should start follow the prompts.


Once the installation has completed and you have set your mac up

you can then restore only your personal information from the back up

you made prior.

Do not restore any system or library files, this will put Big Sur back on your mac.

Do not restore apps, this will put the Big Sur versions back on your mac which

will not work on Mojave.

Only restore your personal data, but this comes with possible problems too.

Any files you edited or created in Big Sur may not be backwards compatible

with the Mojave versions of apps.

If you opened your Photos library and Music library in Big Sur and upgraded

these libraries to work with Big Sur you cannot downgrade them back to a

version that will work with Mojave.



7 replies
Question marked as Top-ranking reply

Sep 23, 2021 11:46 PM in response to JGalt60

Before you upgrade to a new OS like macOS Big Sur it is vital you check that any apps that you use with your mac will

continue to work with the new OS. This is especially true because from the introduction of macOS Catalina two

years ago new mac OS's no longer run 32bit apps, and this will continue in future macOS's.

Before upgrading it would have been helpful for you to download and run this free app, https://www.stclairsoft.com/Go64/

This will list all your apps that are 32bit or have 32bit elements, and you can contact the apps developers to see if

they are providing 64 bit updates or alternatives. The same also applies for any printers/ scanners or other hardware you use

with you mac. You can still run the app now, and then check for updates.


Unfortunately when you are on macOS Big Sur it will not let you download older macOS full installers like macOS Mojave.


Can you source another mac that is running an older OS which is capable of downloading the macOS Mojave installer.

On that mac,

Open Safari and click on this link, 

How to get old versions of macOS – Apple Support

Go to the Download OS section and click on macOS Mojave.

This will redirect you to the App Store Mojave download page,

it should say Get or Download.

Once it has completed downloading.

Make a bootable USB installer using these instructions,

How to create a bootable installer for macOS – Apple Support (UK)


Now make a full back up of your mac.


Insert the bootable USB directly to your mac.


Restart your mac while pressing and holding down the option/ alt key.

In about two minutes you will see the Boot Manager, select the USB and

press Return. The mac will now boot to the USB.

From the Utilities panel select Disk Utility and press Continue.

Click View in the menubar and select Show All Devices.

Highlight the Disk (Apple HDD..... or similar) not any of the indented Volumes.

Click Erase.

Give the Disk a name.

Format: APFS.

Scheme: GUID Partition Map.

Click Erase.

When Done quit Disk Utility.


Click on Install OS and press Continue.

The installation procedure should start follow the prompts.


Once the installation has completed and you have set your mac up

you can then restore only your personal information from the back up

you made prior.

Do not restore any system or library files, this will put Big Sur back on your mac.

Do not restore apps, this will put the Big Sur versions back on your mac which

will not work on Mojave.

Only restore your personal data, but this comes with possible problems too.

Any files you edited or created in Big Sur may not be backwards compatible

with the Mojave versions of apps.

If you opened your Photos library and Music library in Big Sur and upgraded

these libraries to work with Big Sur you cannot downgrade them back to a

version that will work with Mojave.



Sep 23, 2021 7:40 PM in response to JGalt60

JGalt60 Said:

"Reinstall Mojave: Recently installed Big Sur on my 2014 MBP but doesn't play well with some of my apps. Tried to reinstall Mojave but downloader would not install stating that I have the most recent OS. Can't use Time Machine as this is on an external drive which won't open in Big Sur. Anybody know a workaround?"

-------


Verify Compatibility:

2014 MBP Compatible Versions:***

  • MacBook Pro (Retina, 15-inch, Mid 2014)
  • MacBook Pro (Retina, 13-inch, Mid 2014)


***Source: macOS: macOS Big Sur is Compatible with these Computers - Apple Support


Find the Model Info Here:

  1. Go to: Apple menu
  2. Select: About This Mac
  3. View: Second item-down

Is it compatible?

Sep 24, 2021 1:15 PM in response to JGalt60

JGalt60 Said:

"Reinstall Mojave: Big Sur is compatible but I do not want it. I would like to reinstall Mojave.

———-


See if this Site Helps: How to Reinstall the macOS Anew - No TMB Prior to Upgrade - User Tip. Because you would not be upgrading, put aside: Step D


In Depth:

Pretty much, it is a matter of:

  1. Erasing: and formatting your hard drive to APFS
  2. Installing: Mojave via a USB Bootable Installer
  3. Restoring: info from a Time Machine Backup, using Migration Assistant.

Sep 24, 2021 6:48 AM in response to JGalt60

Well you asked for help.


Is there no one you know who is running a mac with an older OS

so they can download the Mojave installer app then make a bootable installer.


There is something else you could try, as it is a 2014 Mac you could download Mac OS X El Capitan 10.11,

not downloads differently to newer OS's, then crate a bootable installer, erase your mac

install that and then upgrade to macOS Mojave 10.14.6.


Try this,

If you do have an operating system on your mac and it is functioning then you can download

El Capitan using this method.


How to get old versions of macOS – Apple Support

Go to Download OS and click on OS X El Capitan 10.11

this downloads InstallMacOSX.dmg to your Downloads folder.


The next section can only be done on a mac that is capable of running El Capitan.

This includes macs that have the potential to run El Capitan but have been upgraded to a newer OS.

A mac that came preinstalled with an OS later than El Capitan 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 El Capitan

but converts the InstallMacOSX.pkg to the Install OS X El Capitan.app which 

you will find in your Applications folder, it should be 6.2GBs in size.


(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 El Capitan on, that is for later.)


Create a bootable USB installer disk using the Install OS X El Capitan.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


If your 2014 mac with Big Sur allows you do this then get back to me and then I can give you further "lectures"

on how to erase and reformat your mac to Mac OS Extended (Journaled) so you can then install Mac OS X El Capitan 10.11.6.

Once you have installed El Capitan you will be able to download the macOS Mojave installer app, and either do a clean install

of Mojave or an in place install of Mojave over the existing El Capitan install.


If you can download El Capitan and convert it to the Install OS X El Capitan.app and create a bootable USB installer.

Stop there for the moment there is something I need to check first as I need to check whether or not the Disk Utility

in El Capitan can actually reformat an APFS formatted drive. We may have to go for macOS Sierra.


I'll get back to you soon.

Reinstall Mojave

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