Failed Catalina boot stick creation; High Sierra no problem

[landshark2]

I'm using a mid 2012 15" MBP running High Sierra, and following the Macworld guide to boot stick creation, the copy / paste of the High Sierra text for use in terminal mode was successful in creating a High Sierra boot stick. That is for my mid 2010 27" iMac. I also have a mid 2012 13" MBP, which will be the first customer for a clean Catalina install. But following the same steps as with High Sierra, the Catalina attempt resulted in this response from terminal mode...

/Applications/Install macOS Catalina.app does not appear to be a valid OS installer application.

So then I went to the Apple page on boot stick creation and did the copy / paste from there, but still the same response.

I am seeking any theories on why the Catalina boot stick creation failed?

Thanks

 

[bogdanw]

Check the size of the Install macOS Catalina.app, re-download if it's just a few MB.

Download Catalina https://apps.apple.com/app/id1466841314

Apple Support - Create a bootable installer for macOS
https://support.apple.com/en-us/HT201372
https://support.apple.com/HT201372
For Catalina

sudo /Applications/Install\ macOS\ Catalina.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

 

[aespana]

I think you can't create a bootable USB of Catalina using High Sierra since there isn't a Update Manager like Mojave+.

If it is a Macbook Pro 2012, you can install it using internet recovery

 

[landshark2]

I've decided to upgrade my 15" MBP to Catalina, in order to facilitate the creation of a Catalina boot stick. I was going to skip this step, and eventually do a clean Catalina install on a new ssd in the 15", but my only other computer is an M1 Mini running Ventura, and it doesn't seem that the App Store will allow the Catalina installer to be downloaded to that Mac.

 

[Grumpus]

I've decided to upgrade my 15" MBP to Catalina, in order to facilitate the creation of a Catalina boot stick. I was going to skip this step, and eventually do a clean Catalina install on a new ssd in the 15", but my only other computer is an M1 Mini running Ventura, and it doesn't seem that the App Store will allow the Catalina installer to be downloaded to that Mac.

Catalina Patcher can download Catalina from Apple's servers. You don't have to create a patched installer after the download if you don't need it. Watch the tutorial video. Other possibilities for getting it downloaded are listed here.

 

[landshark2]

Once again, I am failing at creating a Catalina boot stick.

I did upgrade my mid 2012 15" MBP to Catalina, and now I can't figure our how to download the Catalina downloader from the App Store. It just goes straight to updating the system software. I will now start a new thread about creating a Catalina boot stick with a Mini running Ventura.

 

[aespana]

Go to this link: https://support.apple.com/en-gb/HT211683

- Select Catalina and the link will open the App Store
- Click on Download
- The Update Manager will open asking you to download Catalina
- Click on Download and let the Update Manager do his job
- After the download is completed, he will tell you a message of error and then, the installer will be available in the launchpad and now you can use an usb and put the terminal command

Remember that you need to fully update Catalina before this so, check if there are any updates before doing this. If not, he will try to update your system

 

[landshark2]

aespana nailed it with the final blurb - Fully Update Catalina!

Catalina boot stick creation went fine after I got fully updated.

 

[aespana]

aespana nailed it with the final blurb - Fully Update Catalina!

Catalina boot stick creation went fine after I got fully updated.

Nice man! Glad that you finally make it work!

Yeah, I did a lot, really a lot of USB sticks to install different versions of Mac OS to my humble Macbook 12" :"). Poor thing.