You can make a difference in the Apple Support Community!

When you sign up with your Apple Account, you can provide valuable feedback to other community members by upvoting helpful replies and User Tips.

Looks like no one’s replied in a while. To start the conversation again, simply ask a new question.

Formatting 32G Flash Drive for OS X El Capitan Install?

First Question:

Would it be most optimal to reformat my SanDisk Ultra (USB 3.0) Flash Drive from its currently a) MS-DOS (FAT32) format & 1) Master Boot Record partition map to any other formats like b) Mac OS Extended (Journaled) or c) ExFAT ; or to any other partition maps such as 2) GUID or 3) Apple Partition Maps?


These were possible solutions to my previous related questions:

1https://discussions.apple.com/thread/251450852?answerId=252850825022#252850825022

2Link to this Post


Second Question:

My next question concerns the text boxed-in light blue border in the image below. How do I go about making sure my OS X or Mac OS Installers are bootable installers? Does this pertain to a Bootable Installer only when on a CD-ROM(CD-R/WR), a DVD-ROM(DVD-R/WR), a flash drive, or all three? Link to the post in the image is below.

Link to this Post

iMac Pro

Posted on Aug 6, 2020 5:13 AM

Reply
Question marked as Top-ranking reply

Posted on Aug 6, 2020 10:13 PM

1) Here is the Apple article with instructions on how to create a bootable macOS USB installer. In the article it states the USB drive must be erased as GUID partition and MacOS Extended (Journaled).

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


2) If the Terminal command completes successfully, then you can try booting the USB installer by Option Booting the Mac by holding down the Option key just after the startup chime (on older Macs) or immediately after powering on the a newer Mac. If the USB installer doesn't boot, then perhaps you have a bad or incompatible USB stick (the quality of USB sticks is extremely poor and Macs can be a bit picky about the USB sticks used for booting).


I highly recommend you have a good backup before trying to install or upgrade macOS just in case something goes wrong so you don't lose access to your data.

Similar questions

2 replies
Question marked as Top-ranking reply

Aug 6, 2020 10:13 PM in response to RAMSKULL

1) Here is the Apple article with instructions on how to create a bootable macOS USB installer. In the article it states the USB drive must be erased as GUID partition and MacOS Extended (Journaled).

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


2) If the Terminal command completes successfully, then you can try booting the USB installer by Option Booting the Mac by holding down the Option key just after the startup chime (on older Macs) or immediately after powering on the a newer Mac. If the USB installer doesn't boot, then perhaps you have a bad or incompatible USB stick (the quality of USB sticks is extremely poor and Macs can be a bit picky about the USB sticks used for booting).


I highly recommend you have a good backup before trying to install or upgrade macOS just in case something goes wrong so you don't lose access to your data.

Formatting 32G Flash Drive for OS X El Capitan Install?

Welcome to Apple Support Community
A forum where Apple customers help each other with their products. Get started with your Apple Account.