How to Download Adobe Flash Player. Click on the DOWNLOAD button on the sidebar to jump straight to the Adobe download page. Before clicking the INSTALL NOW button, you can choose to accept or refuse the two McAfee optional offers. Before the program installs, you can set your update preferences. Some flash drives have to be formatted first before you can store files on them. In this article, we are taking a closer look at the Disk Utility, which comes with all recent versions of the Mac OS X operating system and how you can use it to format USB drive on Mac. Format Flash Drive Mac with Disk Utility. Your Mac computer comes with a handy. Download the EaseUS Mac USB cloning software from the link above, insert both your flash drives on the computer, and run EaseUS Todo Backup for Mac to clone the USB drive. In the 'From' drop-down list, select the volume you want to clone, which should be the source USB flash drive.

I purchased a used 2018 Mac mini desktop and wanted to put a fresh installation of the latest macOS 10.15 Catalina on it. Below are the steps I took.

  1. Sep 21, 2021 How To Download From Flash Drive To Mac. Insert the flash drive into one of your computer’s USB ports. Laptops, like cameras, often. Flash Drive Maker helps you make your own bootable USB drives via the command line without having to look for the correct commands, manually setting the path to the source installers, and so on.
  2. Learn how to copy files from Windows 8 PC to a Mac OS X computer using external flash drive formatted in FAT32 file system.Don't forget to check out our site.

Note: The instructions below are the same for macOS 10.13 High Sierra and macOS 10.14 Mojave.

Download macOS Catalina

You will need a Mac to download macOS Catalina; you can download Catalina from The Mac Go. (The Mac mini came with macOS 10.14 Mojave so I used it to download Catalina.)

Go to the Mac App Store, search for “macOS Catalina”, and download it. It will be saved to the “/Applications/Install macOS Catalina” location. If the installer automatically launches, just close it.

Note: If you plan to run the installer first to update your current macOS version to Catalina, you will want to move the “Install macOS Catalina” application out of the “/Applications” directory; otherwise, the installer will delete itself from the “/Applications” directory when the upgrade completes. For example, you can move the “Install macOS Catalina” application to the “~/Downloads” directory and run it from there.

Format USB Flash Drive

Because macOS Catalina is 8.4GB in size, you will need a 16GB USB flash drive. You don’t need to delete the existing content on the drive because we will blow it all away in a subsequent step.

If the USB flash drive is not already formatted as “Mac OS Extended (Journaled)”, format it like so:

  1. Plug the USB flash drive into your Mac.
  2. Launch the “Disk Utility” application.
  3. On the left-hand pane, select the USB drive (not the partition under it, if any).
  4. Click on the “Erase” tab (or button at the top).
    1. Input a name like “Catalina” (this name will be overwritten later).
    2. Select “Mac OS Extended (Journaled)” for “Format”.
    3. If available, select “Master Boot Record” for “Scheme”.
    4. Click the “Erase” button at the bottom. Click the “Erase” button in the warning popup dialog if you get one.
  5. The format operation may take several minutes to complete. (USB 2.0 and large capacity drives may take longer.) After the format completes, the partition will be mounted under “/Volumes/Catalina” (or whatever name you selected above).
  6. Close the “Disk Utility” application.

Write macOS Catalina to USB Flash Drive

To create a bootable USB macOS Catalina installer, run the “Terminal” application and this command:

# The --volume value is the mounted USB flash drive partition; in this case, named /Volumes/Catalina
sudo/Applications/Install macOS Catalina.app/Contents/Resources/createinstallmedia --volume/Volumes/Catalina
# You will be prompted for your user's administrative password.

Note: If the createinstallmedia command returns a “Failed to start erase of disk due to error (-9999, 0)” error, then your current Mac OS X version does not fully support the createinstallmedia tool. Use a more recent macOS version (at least Mac OS X 10.11 El Capitan) or manually create the USB installation drive using instructions from Bootable USB Flash Drive to Install Mac OS X 10.10 Yosemite.

The “createinstallmedia” program will erase the USB flash drive, create a new partition named “Install macOS Catalina”, and copy the installation files to that partition. The output will look like:

Erasing disk: 0%... 10%... 20%... 30%... 100%
Copying to disk: 0%... 10%... 20%... 30%... 40%... 50%... 60%... 70%... 80%... 90%... 100%
Making disk bootable...
Copying boot files...
Install media now available at '/Volumes/Install macOS Catalina'

The above process took 20-30 minutes using my Kingston USB 2.0 flash drive.

Boot From USB Flash Drive

Download Flash Drive To Mac

Note: Apple’s How to create a bootable installer for macOS page suggest using the “Startup Disk” configuration (under “System Preferences”) to select the USB flash drive as the startup drive. Then on restart, the Mac should boot from the USB flash drive. Unfortunately, the “Startup Disk” did not list my USB flash drive as a startup option, so I was not able to use this method.

To boot a Mac with the USB flash drive:

  1. Insert the USB flash drive.
  2. While holding the “option” key down, turn on the Mac to display the Startup Manager.
  3. You should see one or more icons, one of which should be called “Install macOS Catalina” for the USB flash drive. (The internal hard drive may not be visible if it does not have a valid, bootable partition installed.)
    • Note: If you don’t see the USB flash drive’s “Install macOS Catalina”, try removing and re-inserting the USB flash drive while viewing the Startup Manager screen. The USB flash drive should then appear after a few seconds.
  4. Select the “Install macOS Catalina” (with left/right arrow keys) and hit the “return/enter” key to boot from the USB flash drive.

It may take 5-10 minutes to load the installer from the USB flash drive. Sometimes the progress bar may appear to be frozen or the screen will go black for a minute or two. Be patient.

External Startup Disk Not Allowed

On a newer Mac with the T2 security chip, booting from an external drive may be disallowed by default. Attempting to boot from a USB flash drive will result in a “Security settings do not allow this Mac to use an external startup disk” warning message.

To allow booting from the USB flash drive, do the following:

  1. Hold down “Command-R” (hold down both the “Command ⌘” and “R” keys) when you start the Mac to launch macOS Recovery. You can release the keys when you see the Apple logo.
    • Tip: An easier alternative is to hold the “Option/Alt” key on boot to launch the Startup Manager. Then just click and release “Command-R” keys to launch macOS Recovery.
  2. The macOS Recovery screen contains a top-level “macOS Utilities” menu.
  3. Click on the “Utilities” menu and select “Startup Security Utility”. Input your administrator password when prompted.
  4. In the Startup Security Utility, under “Allowed Boot Media”, select the “Allow booting from external or removable media” option.
  5. If the Mac won’t have access to the Internet (either by wire or wirelessly) when installing macOS Catalina, make sure to select either the “Medium Security” or “No Security” option under the “Secure Boot” section. (You can change the option back to the default “Full Security” afterwards.)
  6. Quit the macOS Utilities to restart the Mac.
  7. On restart, follow the directions in the previous section to boot from the USB flash drive.

Using Flash Drive On Mac

Erase the Internal Hard Drive

When the installer finishes loading, you will see a “macOS Utilities” screen appear. It looks the same as the “macOS Recovery” screen with one difference. In the “macOS Utilities” window, the second option will say “Install macOS” instead of “Reinstall macOS”. In “macOS Recovery”, the “Reinstall macOS” option would just re-install the same version of macOS. The “Install macoS” option will install the macOS Catalina version on the USB flash drive.

Before installing macOS, I wanted a clean slate so I erased the internal hard drive like so:

  1. Select the “Disk Utility” option and click the “Continue” button on the bottom to launch the “Disk Utility” application.
  2. On the left-hand pane, select the internal hard drive (not the partition under it, if any).
  3. Click on the “Erase” button at the top.
    1. Keep the default “Macintosh HD” name or input a new one.
    2. Select “APFS” for “Format”.
    3. Click the “Erase” button at the bottom. The SSD (Solid State Drive) format took less than a minute to complete.
  4. Close the “Disk Utility” application.

Install macOS Catalina

Warning: If your Mac has a T2 security chip and you left the “Full Security” option configured in the Startup Security Utility, make sure that Internet access (wired or wireless) is available before starting the macOS Catalina installation. You can configure the wireless network by clicking on the wireless icon at the top-right corner of the macOS Utilities screen.

Back at the “macOS Utilities” window, do the following to start the macOS Catalina installation:

  1. Click on the “Install macOS” option and click the “Continue” button.
  2. The “macOS Catalina” installer’s splash screen will appear. Click the “Continue” button.
  3. Click on the “Agree” button to agree to the license. A popup confirmation window will appear; click on the popup’s “Agree” button.
  4. Select the internal hard drive and click the “Install” button.

My Mac mini took 20-30 minutes to complete the macOS Catalina installation. I think there were a couple of reboots in-between. And a few times, the screen would go black for a minute or two. Be patient and give the process an hour or more to complete.

If you run into problems installing macOS Catalina, check the “What Does Giving Up Mean?” section (at the bottom) of Install macOS Sierra Using Bootable USB Flash Drive for possible solutions.

Note: macOS Catalina seems to have an issue with my Dell 24in U2410 monitor. During the initial bootup screen, the monitor shows a blank screen with a message, “The current input timing is not supported by the monitor display”. Thankfully, the monitor works correctly after the bootup completes. And later, this warning message no longer appeared on bootup.

Enjoy your fresh installation of macOS 10.15 Catalina.

Download Flash Drive To Mac

To perform a clean installation of macOS Sierra (basically, Mac OS X 10.12), I recommend using a bootable USB flash drive containing the macOS Sierra installer. Below are the steps I took to create the bootable USB flash drive and how I used it to install macOS Sierra.

Note: The macOS Sierra Disk Utility and installer appears to be more buggy and much slower than previous versions. The best advice for installing macOS Sierra is to try again and be very patient (if you expect an operation to complete in 5 minutes, then give it at least 50 minutes).

Download macOS Sierra Installer

The macOS Sierra installer is available from the Mac App Store. Run the “App Store” application, search for “macOS Sierra”, and download it. It will save the installer as an “/Applications/Install macOS Sierra.app” file (about 4.97GB in size).

Note: If you run the macOS Sierra installer to upgrade your Mac, the downloaded file will be deleted automatically after the upgrade is completed. To keep that file, you will want to move it out of the Applications folder so it won’t be deleted after an upgrade. Launch the “Terminal” application and run this command to move the downloaded installer to your user’s “Downloads” folder:

sudomv/Applications/Install macOS Sierra.app/ ~/Downloads/

If you are paranoid (doesn’t hurt), you can verify that the installer file was downloaded correctly by verify its checksum. Run the “Terminal” application and this command:

hdiutil verify /Applications/Install macOS Sierra.app/Contents/SharedSupport/InstallESD.dmg
# If successful, the last output line should read:
# hdiutil: verify: checksum of '/Applications/Install macOS Sierra.app/Contents/SharedSupport/InstallESD.dmg' is VALID

Format USB Flash Drive

The macOS Sierra installer takes up 5.1GB of space on the USB flash drive, so you will need a flash drive with a capacity of 8GB or greater.

Note: If the flash drive is mounted under “/Volumes” successfully when you plug it in, you can skip the following steps to reformat the flash drive. This is because the script we run to create the bootable drive will reformat the flash drive as an initial step. Because I am paranoid, I recommend reformatting the USB flash drive manually anyhow.

Format the USB flash drive using these steps:

  1. Plug the USB flash drive into your Mac.
  2. Launch the “Disk Utility” application.
  3. On the left-hand pane, select the USB drive (not the partition under it, if any).
  4. Click on the “Erase” tab (or button at the top).
    1. Input a name like “Sierra” (this name will be overwritten later).
    2. Select “Mac OS Extended (Journaled)” for “Format”.
    3. Select “Master Boot Record” for “Scheme”.
    4. Click the “Erase…” button at the bottom. Click the “Erase” button in the warning popup dialog if you get one.
      • The format operation may take several minutes to complete. (USB 2.0 and large capacity drives will take longer.) After the format completes, the partition will be mounted under “/Volumes/Sierra” (or whatever name you selected above).
      • Note: Under macOS Sierra, the Erase function will fail if the USB drive’s partition is mounted. You can manually unmount the partition before running Erase. Or you can run Erase twice; the first time will unmount the partition and fail, and the second time will actually do the format (which will succeed).
  5. Close the “Disk Utility” application.

Create Bootable USB Flash Drive Installer

To create the bootable USB macOS Sierra installer, run the “Terminal” application and this command:

# The --volume value is the mounted USB flash drive partition; in this case, named /Volumes/Sierra
sudo/Applications/Install macOS Sierra.app/Contents/Resources/createinstallmedia --volume/Volumes/Sierra --applicationpath/Applications/Install macOS Sierra.app --nointeraction
# You will be prompted for your user's administrative password.

Update: For macOS 10.14 Mojave (and its predecessor, macOS 10.13 High Sierra), the createinstallmedia command no longer requires the “–applicationpath” and “–nointeraction” flags, so omit them. The command becomes just “createinstallmedia –volume /Volumes/Mojave”.

Note: If the createinstallmedia command returns a “Failed to start erase of disk due to error (-9999, 0)” error, then your current Mac OS X version does not fully support the createinstallmedia tool. Instead, create the USB installation drive manually using instructions from Bootable USB Flash Drive to Install Mac OS X 10.10 Yosemite.

The “createinstallmedia” program will erase the USB flash drive, create a new partition named “Install macOS Sierra”, and copy the installation files to that partition. The output will look like:

Erasing Disk: 0%... 10%... 20%... 30%...100%...
Copying installer files to disk...
Copy complete.
Making disk bootable...
Copying boot files...
Copy complete.
Done.

The program will pause at the “Copying installer files to disk…” output line above. This step took 20-30 minutes with my Kingston 16GB USB 2.0 flash drive. Yours may take a shorter or longer time. I recommend giving it at least an hour, maybe two, before giving up.

Note: Mac hardware is very finicky about USB flash drives. Initially, I used a Corsair 32GB USB 3.0 drive; however, when I held down the Option key to try to boot with it, the Mac would freeze with a black startup screen. The Kingston 16GB USB 2.0 drive did not have this problem. So if you enounter issues (when erasing and copying) or weirdness (when booting), consider changing to another brand of USB flash drive. If you don’t have another drive, consider at least testing the flash drive to make sure it is not bad or corrupted (“First Aid” in “Disk Utility” is the minimum; google for more powerful tools).

Boot With USB Flash Drive

Note: I recommending connecting the Mac to its AC power adapter before beginning the macOS Sierra installation. The installation may take a long time (an hour or more) and you don’t want the battery to die in the middle.

To boot a Mac with the USB flash drive:

Download flash drive to my computer
  1. Shutdown the Mac.
  2. Insert the USB flash drive.
  3. While holding the “option/alt” key down, turn on the Mac to display the boot Startup Manager.
  4. You should see one or more icons, one of which should be called “Install macOS Sierra” for the USB flash drive. (The internal hard drive may not be visible if it does not have a valid, bootable partition installed.)
    • Note: If you don’t see the USB flash drive’s “Install macOS Sierra”, try removing and re-inserting the USB flash drive while viewing the Startup Manager screen. The USB flash drive should then appear after a few seconds.
  5. Select the “Install macOS Sierra” (with left/right arrow keys) and hit the “return/enter” key to boot from the USB flash drive.

It may take 5-10 minutes or longer to load the installer from the USB flash drive. Sometimes the progress bar may appear to be frozen… just be patient. I would give it at least 30-60 minutes to load before giving up.

Format the Hard Drive

Download Flash Drive To Mac

When the installer finishes loading, you will see a “macOS Utilities” window appear. Do the following to format the internal hard drive:

  1. Click on the “Disk Utility” option and click the “Continue” button on the bottom to launch the “Disk Utility” application.
  2. On the left-hand pane, select the hard drive (not the partition under it, if any).
  3. Click on the “Erase” button at the top.
    1. Input a name like “macOS”.
    2. Select “Mac OS Extended (Journaled)” for “Format”.
    3. Select “GUID Partition Map” for “Scheme”.
    4. Click the “Erase…” button at the bottom.
      • For SSD (Solid State Drive), the format operation may take less than a minute to complete. For mechanical hard drive, it may several minutes to hours, depending upon the size, speed, and condition of your hard drive.
      • Note: Again, the Erase function will fail if the hard drive’s partition is mounted. You can manually unmount the partition before running Erase. Or you can run Erase twice; the first time will unmount the partition and fail, and the second time will actually do the format (which will succeed).
  4. Close the “Disk Utility” application.
Download Flash Drive To Mac

Download Files From Flash Drive To Mac

Note: Now and then, I noticed the output of the Erase seems to erroneously double the size of the hard drive. For a 128GB hard drive, the graph shows 120.88GB macOS (in blue) and 120.37 GB Unformatted (in red). I think it is just a user interface bug because when I close Disk Utility and re-open it, the graph then only shows the 120.88GB macOS (in blue).

Install macOS Sierra

Back at the “macOS Utilities” window, do the following to begin the macOS Sierra installation process:

  1. Click on the “Install macOS” option and click the “Continue” button.
  2. The “macOS Sierra” installer’s splash screen will appear. Click the “Continue” button.
  3. Click on the “Agree” button to agree to the license. A popup confirmation window will appear; click on the popup’s “Agree” button.
  4. Select the hard drive and click the “Install” button.

Note: You may encounter strange hardware behavior. On my 13 inch Macbook Pro Retina, the macOS Sierra installer turned the fan on to maximum for the whole duration of the installation. Thankfully, once it finished and rebooted, the fan turned off and stayed off.

The macOS Sierra installer tries to be helpful by telling you how long it will take. Unfortunately, it lies. You should take whatever remaining time it tells you and multiple by 10 (for minutes) or 100 (for seconds). If it says “6 minutes remaining”, that could mean 60 minutes or one hour remaining. Worse, if it says “6 seconds remaining”, you may be staring at that message for 600 seconds or one hour.

The best solution is to be patient. Go grab a bite to eat and watch a movie. Take a long nap or better yet, sleep your 8 hours. I would wait at least 4 hours before giving up.

Note: You can display the installer’s log window (using the menu or pressing Cmd+L). I didn’t find this helpful at all. Even for a successful install, numerous errors are logged; I don’t know what is a critical or non-critical error. And often, you won’t see a progress/status log output for a long time, easily 20-30 minutes. Not seeing any new log statements does not mean that the installer froze. So the logs didn’t do anything for me.

What Does Giving Up Mean?

Giving up means you have accepted defeat. The next step is to retreat and try again. Some suggestions on how to proceed:

  • Reset your Mac by doing the following:
    1. Reset the SMC (see step 3 under the “Reset the SMC on Mac notebook computers” section).
    2. Reset the NVRAM (aka PRAM).
    3. Run the Apple Hardware Diagnostic or Test to make sure you don’t have a hardware failure.
    4. Finally, retry the macOS Sierra install.
  • Use a different USB port on the Mac.
  • Use another brand of USB flash drive.
  • Delete and re-download the macOS Sierra installer (especially if you downloaded it a long while ago). Even if the checksum is okay, you may want to re-download in case there is a newer version of the installer with a bug fix for your very problem.
  • Download an older Mac OS X version, say Mac OS X 10.11 El Capitan, install that, and then upgrade to macOS Sierra. If you know the Mac OS X version which came with your Mac originally, consider downloading (if you still have access) and installing that version first.
  • Use the Mac Recovery System to download and install the original OS version that came with your Mac. Then upgrade from that to macOS Sierra.
  • Buy a more recent model Mac (at most a couple of years old). It may be that your current Mac is too old or slow to support macOS Sierra. It’s okay to keep running an old Mac OS version. (For example, if I had a Core 2 Duo Mac, I would not run anything later than Mac OS X 10.9 Mavericks on it.)

Hopefully, this post will help you to do a fresh installation of macOS Sierra.

Some info above taken from: