Catalina on Imac Late 2013's not booting USB sticks

[Zourous]

We have Imac's in our Media Suite with MacOS (recently upgraded to Catalina) and Windows 10 installed on a separate partition.

 

Since the upgrade to Catalina it seems USB sticks that I boot off into a WinPE to restore and upgrade the Windows partitions has stopped working.

 

Suspiciously the USB sticks shows up as a Hard drive icon and not as a USB icon like before on the boot screen. When you try to boot you get the "Non bootable device -- insert boot disk..." message

 

Anyone know what's going on here?

 

The same stick boots fine on another imac with no MacOS or an older MacOS on it.

[AntonioRocco]

Perhaps your issue is to do with Apple's Security Boot feature introduced since the T1 & T2 chipsets were made available?

 

https://support.apple.com/en-us/HT208198

 

I think the 3rd option on the Secure Boot part of the menu might help? Good luck!

[Zourous]

Perhaps your issue is to do with Apple's Security Boot feature introduced since the T1 & T2 chipsets were made available?

 

https://support.apple.com/en-us/HT208198

 

I think the 3rd option on the Secure Boot part of the menu might help? Good luck!

 

Nice idea but these are older late 2013 macs. Everything in the link is more recent. Any how thanks for replying. I haven’t got much experience with macs so I could be missing something

[AntonioRocco]

I remember seeing something similar about 10 years ago. Turned out to be the management software the school was using had somehow imposed a restriction on booting from USB attached drives. It's a long shot but have a look at what you're using to manage the Macs. Perhaps the issue is there?

 

On another note I would always do a nuke and pave upgrade to a newer OS rather than an in place upgrade of an older OS. It's a bit more work but saves you potential headaches in the longer run.

Edited December 19, 2021 by AntonioRocco

[Zourous]

You might have something there. My boss had recently purchased jamf and set it up. I have no idea what it can and can’t do. I’ll check after xmas. Thanks