Help! How do I create a Mojave bootable thumb drive while I am running Catalina

[paulwgraber]

Ok so I have posted this before and actually had it working at one point but since forgot and lost my micro usb 3.0 thumb drive so I have to start over.

I am running Catalina. I want to create a Mojave bootable external micro usb drive. I have used Diskmaker X (doesn't work). So can somebody give me explicit instructions on how to do this please. I have the install Mojave app. When ever I try to in stall anything I get the newer os BS message. Cant find a Mojave boot image anywhere either. I have two USB drives but can't get the image on one to show up in my startup disk.

Help. Thanks.

 

[CoastalOR]

Here is Apple's instructions on creating a bootable installer with a link to macOS Mojave:

Create a bootable installer for macOS - Apple Support

Use an external drive or secondary volume as a startup disk from which to install macOS.

support.apple.com

 

[paulwgraber]

I am but it won't show up as a startup disk. Even when using disk make X.
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I am using SSD Seagate drive with an 8 G partition to create a boot image with disk maker. Will not show up as a start up disk still.

 

[CoastalOR]

I am but it won't show up as a startup disk. Even when using disk make X.

If you are replying to my post then...
I understood from your 1st post that Diskmaker X isn't working for you, so I did not mention it.
The link I posted does not use/mention Diskmaker X, instead the linked Apple instructions references "Use the 'createinstallmedia' command in Terminal" to create the installer drive.

 

[paulwgraber]

OK I will give that a shot and let you know. Thx
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I keep getting this in terminal


Kerrys-iMac:~ paulgraber$ sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/install mojave


Password:


/Volumes/install is not a valid volume mount point.

Where install Mojave is the portion I created on my external disk.

 

[CoastalOR]

OK I will give that a shot and let you know. Thx
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I keep getting this in terminal


Kerrys-iMac:~ paulgraber$ sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/install mojave


Password:


/Volumes/install is not a valid volume mount point.

Where install Mojave is the portion I created on my external disk.

The terminal command is wrong for the name of the USB drive, it is looking for the drive name to be "install". I would recommend (temporarily) changing the name of your USB drive to "installmojave" (all one word).

Then use:
sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/installmojave

You can rename your USB drive anything you want after the Mojave installer is successfully created.

 

[Taz Mangus]

OK I will give that a shot and let you know. Thx
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I keep getting this in terminal


Kerrys-iMac:~ paulgraber$ sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/install mojave


Password:


/Volumes/install is not a valid volume mount point.

Where install Mojave is the portion I created on my external disk.

Change the command line to:

sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/install\ mojave

You need a backslash in front of the space (use install\ mojave instead of install mojave).

 

[paulwgraber]

Awesome. Went ahead and made a partition on my harddrive so it would be faster. Thx guys. So far so good.