OS X Installation USB not detected in Startup Disk selection

Question

I have a MacBook Pro 8.2. Recently I have download Sierra and Yosemite, and am currently running El Capitan.

And I created a bootable USB for OS X Yosemite with DiskMaker X 6, in case Sierra goes wrong.

But when I try to check the USB, it's not on Startup Disk. I tried the option key on mac boot, but the USB is not there.

I'm using SanDisk Cruzer Glide Media, here the USB details.

Answer 1

From the last image you posted, the window says "Bootable: No". From the screenshot you posted of the files on the USB, this doesn't look like a standard bootable OS X USB. For Yosemite, you could try using Terminal (I'm not sure how Terminal would handle the periods and dashes in your USB's name, so here are the instructions if your USB is named Untitled):

Note that this process automatically erases and formats the USB before moving the files (it normally will confirm this with you), but I like to erase it myself before I do this as a precaution.

sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/Untitled --applicationpath /Applications/Install\ OS\ X\ Yosemite.app

After the process finishes, I believe the USB is named "Install OS X Yosemite"

Source: https://support.apple.com/en-us/HT201372

Answer 2

In order to boot from an external disk it must have a GUID Partition Map. If your USB disk is not formatted with that you will need to reformat it accordingly.

1. Go to Disk Utility
2. Select "Erase"
3. Select GUID from the "Scheme" dropdown menu

Answer 3

Mine does the same thing Terminal says creating bootable.. and it says yes during the make process but later in get info in disk utility it says no for bootable.

I did all kinds of privacy for the file to open anyway and ownership and no matter it just does not boot or flag as bootable with Any method. Diskcreator 6 no go Trans mac no go Terminal says yes but info later says no bootable.

I have downloaded straight from Apple and unpacked to view cert is updated. All 3 of the 2.0 USB sticks installed the same mac oses from Lion to Mojave up until this recert stuff.

Any help on this A1466 EMC2925 Air book would help.