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User profile for user: Al060
Al060 Author
User level: Level 1
4 points

Trying to make a boot thumb drive for keeps failing

Never ran into this issue, trying to make a boot thumb drive of Big Sur keeps failing. Big Slur is installed but mac having some issues so I want to do a clean install. Tried multiple times, using terminal window IMac 2017. See screen grab, background is my thumb drive, front is terminal window, any help would be appreciated


Posted on Jan 23, 2021 9:50 AM

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User profile for user: Jack-19
Jack-19
User level: Level 8
45,716 points

Posted on Jan 23, 2021 8:14 PM

Hi Al060,


I see your issue above; and I want to help. I don't see your screen grab above unfortunately, but I can still offer some suggestions.


First, you don't need a USB Drive to clean install. You can simply use macOS Internet Recovery.


  1. Backup all DATA! When you do this, all your data will be erased! This action cannot be undone! Make sure your are comfortable with where your data is stored besides the Mac. You can use Time Machine, iCloud, or an external hard drive. See this article How to back up your Mac - Official Apple Support
  2. Go to System Preferences, and then Apple ID. Turn off Find My Mac, then sign out of your Apple ID.
  3. Restart the Mac, then when you hear the startup chime, or the screen lights up, immediately press and hold Option + Command + R. Option + Command + R will give you the latest and greatest macOS that your Mac can support. 
  4. Once you are in macOS Recovery, verify you are connected to a WiFi network in the top right corner, and verify your are in macOS Big Sur Recovery. You can tell if the background of the window is black, and you see the macOS Big Sur logo in the "Reinstall macOS" app.
  5. Then go to Disk Utility.
  6. Click the “View” button in the top and select “Show All Devices.”
  7. Select the main hard drive name, not your volumes. For example, select APPLE HDD, APPLE SSD, or Fusion Drive instead of “Macintosh HD.” It will be the top item.
  8. Click erase, and input the following EXACTLY:


Name: Macintosh HD

Format: APFS

Scheme: GUID Partition Map


Now, let's reinstall macOS.

  1. Quit Disk Utility.
  2. Open the macOS Big Sur Installer.
  3. Follow the on-screen instructions and select Macintosh HD as your disk to install to.
  4. Let the process finish, don’t restart, sleep, or shut down your Mac. Also don’t disconnect from WiFi.
  5. Let the process finish; then setup your Mac, and restore your data. For iCloud data, sign into your Apple ID and download data from iCloud. For Time Machine backup and restoring, see this guide: https://support.apple.com/en-us/HT203981. If you copy and pasted your data to an external hard drive, copy and paste the data back. 


I hope this helps. Reach out for more help! If you want Apple's guides, see Erase and reinstall macOS - Apple Support


Cheers,


Jack

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User profile for user: Jack-19
Jack-19
User level: Level 8
45,716 points

Jan 23, 2021 8:14 PM in response to Al060

Hi Al060,


I see your issue above; and I want to help. I don't see your screen grab above unfortunately, but I can still offer some suggestions.


First, you don't need a USB Drive to clean install. You can simply use macOS Internet Recovery.


  1. Backup all DATA! When you do this, all your data will be erased! This action cannot be undone! Make sure your are comfortable with where your data is stored besides the Mac. You can use Time Machine, iCloud, or an external hard drive. See this article How to back up your Mac - Official Apple Support
  2. Go to System Preferences, and then Apple ID. Turn off Find My Mac, then sign out of your Apple ID.
  3. Restart the Mac, then when you hear the startup chime, or the screen lights up, immediately press and hold Option + Command + R. Option + Command + R will give you the latest and greatest macOS that your Mac can support. 
  4. Once you are in macOS Recovery, verify you are connected to a WiFi network in the top right corner, and verify your are in macOS Big Sur Recovery. You can tell if the background of the window is black, and you see the macOS Big Sur logo in the "Reinstall macOS" app.
  5. Then go to Disk Utility.
  6. Click the “View” button in the top and select “Show All Devices.”
  7. Select the main hard drive name, not your volumes. For example, select APPLE HDD, APPLE SSD, or Fusion Drive instead of “Macintosh HD.” It will be the top item.
  8. Click erase, and input the following EXACTLY:


Name: Macintosh HD

Format: APFS

Scheme: GUID Partition Map


Now, let's reinstall macOS.

  1. Quit Disk Utility.
  2. Open the macOS Big Sur Installer.
  3. Follow the on-screen instructions and select Macintosh HD as your disk to install to.
  4. Let the process finish, don’t restart, sleep, or shut down your Mac. Also don’t disconnect from WiFi.
  5. Let the process finish; then setup your Mac, and restore your data. For iCloud data, sign into your Apple ID and download data from iCloud. For Time Machine backup and restoring, see this guide: https://support.apple.com/en-us/HT203981. If you copy and pasted your data to an external hard drive, copy and paste the data back. 


I hope this helps. Reach out for more help! If you want Apple's guides, see Erase and reinstall macOS - Apple Support


Cheers,


Jack

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Trying to make a boot thumb drive for keeps failing

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