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Failed to create bootable Catalina USB in Mojave

Based on https://support.apple.com/en-us/HT201372 I tried twice but both also failed at 100% with the following error:


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


Password:


Ready to start.


To continue we need to erase the volume at /Volumes/Catalina.


If you wish to continue type (Y) then press return: y


Erasing disk: 0%... 10%... 20%... 30%... 100%


Copying to disk: 0%... 10%... 20%... 30%... 40%... 50%... 60%... 70%... 80%... 90%...


Error: Error Domain=NSCocoaErrorDomain Code=512 "“InstallESD.dmg” couldn’t be copied to “SharedSupport”." UserInfo={NSSourceFilePathErrorKey=/Applications/Install macOS Catalina.app/Contents/SharedSupport/InstallESD.dmg, NSUserStringVariant=(


    Copy


), NSDestinationFilePath=/Volumes/Install macOS Catalina/Install macOS Catalina.app/Contents/SharedSupport/InstallESD.dmg, NSFilePath=/Applications/Install macOS Catalina.app/Contents/SharedSupport/InstallESD.dmg, NSUnderlyingError=0x7fa9a35bddc0 {Error Domain=NSPOSIXErrorDomain Code=34 "Result too large"}}The copy of the installer app failed


What went wrong ?


For the past, I've been using https://diskmakerx.com to create bootable USB without any issue. This time around, DiskMakerX still have not release support for Catalina, thus I have to make use of command line.

iMac Line (2012 and Later)

Posted on Oct 9, 2019 6:13 AM

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Question marked as Top-ranking reply

Posted on Oct 12, 2019 3:19 AM

Catalina apparently requires a 16GB USB drive - previous versions would fit on an 8GB drive.

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Failed to create bootable Catalina USB in Mojave

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