After downloading the ISO file, you'll need to use Boot Camp Assistant to move it to a bootable USB drive. Insert a USB flash drive to your Mac. Make sure it's at least 8GB, which is usually marked. So this is the list of the Best Bootable USB software for Windows/Mac 2020 with which you can create a bootable USB drive. If this concept is new to you, Etcher seems to be a good option. On the other hand, if you deal only with Windows, you can go for Rufus or Windows USB/DVD tool.
How to create a bootable macOS Big Sur installer drive Put the macOS Big Sur installer on an external USB thumb drive or hard drive and use it to install the operating system on a Mac. How to create a bootable macOS Catalina installer drive Put the macOS Catalina installer on an external USB thumb drive or hard drive and use it to install the operating system on a Mac.
Connect the external drive to your Mac, and make a note of the external drive's name as it appears within macOS. This is important, as using the wrong name could lead to another connected drive.
To troubleshoot an issue with Windows 10 (especially boot-related issues), it can be handy to boot into Windows 10 not installed on a Boot Camp partition. It is relatively straightforward to create a bootable USB Flash drive to boot to the Windows 10 installer and open up a DOS prompt for troubleshooting.
What is needed
- USB Flash drive (8 GB or larger recommended)
- Windows 10 Installer ISO for Windows 10
Preparation
All the preparation is done in macOS on the Mac that is having an issue booting Windows. https://kpyrx.over-blog.com/2021/01/xbox-on-pc-windows-10.html. It is important to use this Mac since it will be used to identify the correct Windows drivers.
USB Flash Drive
The USB Flash drive must be formatted as exFAT.
- Insert an 8GB or larger flash drive into a USB port on the Mac
- In Disk Utility, format the Flash drive as exFAT. Quit Disk Utility after this operation completes.
Boot Camp Driver
Open Boot Camp Assistant in the Utilities folder and download the current Windows Support Software from the 'Action' dropdown in the menu bar. Save the Windows Support Software to your desktop or other location. Do not save directly to the USB Flash Drive.
Windows Install Media
Download the current install media from the Microsoft website. Windows will not be installed, but the install media will give access to the command line tools in Windows. Select the version of Windows that is closest to the version of Windows installed on the Mac (Windows 8, Windows 10). It does not matter what edition of Windows is used, since Windows is not going to be installed.
Create Recovery USB Flash Drive
To create the USB Flash drive, follow these steps:
- Mount the Windows ISO downloaded from Microsoft. To mount the ISO, double-click on the ISO in Finder.
- Drag all the files and folders from the mounted ISO to the USB flash drive.
- Drag the contents of the Windows Support Software to the USB flash drive.
- If there is not an AutoUnattend.xml at the top level of the drive (as shown below), download AutoUnattend.xml, unzip it, and add it to the drive. AutoUnattend.xml provides the location of the $WinPEDriver$ folder to load the drivers during boot.
- The 2018 MacBook Air (and potentially Macs after that) cannot load the IntelMEI driver and give a 'Windows Setup could not install one or more boot-critical drivers. To install Windows, make sure that the drivers are valid, and restart the installation' message. On the USB flash drive, open the $WinPEDriver$ and remove the IntelMEI folder.
Once the flash drive has been created, it should look like this:
The $WinPEDriver$ folder is important because it contains the drivers for Windows to boot successfully from the USB flash drive and the hardware on that Mac.
Boot from the USB Flash drive
To inject the drivers, the Mac must be booted from the USB flash drive.
- Insert the USB flash drive into an available USB port on the Mac
- Reboot while holding the Option key.
- Select EFI volume in the startup selector.
If Windows does not boot from the USB flash drive after showing the Windows logo, you may have to run the following command to tell the firmware to boot the Windows installer from the USB flash drive. This has been observed on the late-2014 Mac Mini but may affect other models as well. To set the variable:
- Disable SIP by booting to the recovery partition.
- Boot back to macOS and open Terminal. Run the following command and enter the admin password when prompted:
sudo nvram InstallWindowsUEFI=1
- USB Flash drive (8 GB or larger recommended)
- Windows 10 Installer ISO for Windows 10
Preparation
All the preparation is done in macOS on the Mac that is having an issue booting Windows. https://kpyrx.over-blog.com/2021/01/xbox-on-pc-windows-10.html. It is important to use this Mac since it will be used to identify the correct Windows drivers.
USB Flash Drive
The USB Flash drive must be formatted as exFAT.
- Insert an 8GB or larger flash drive into a USB port on the Mac
- In Disk Utility, format the Flash drive as exFAT. Quit Disk Utility after this operation completes.
Boot Camp Driver
Open Boot Camp Assistant in the Utilities folder and download the current Windows Support Software from the 'Action' dropdown in the menu bar. Save the Windows Support Software to your desktop or other location. Do not save directly to the USB Flash Drive.
Windows Install Media
Download the current install media from the Microsoft website. Windows will not be installed, but the install media will give access to the command line tools in Windows. Select the version of Windows that is closest to the version of Windows installed on the Mac (Windows 8, Windows 10). It does not matter what edition of Windows is used, since Windows is not going to be installed.
Create Recovery USB Flash Drive
To create the USB Flash drive, follow these steps:
- Mount the Windows ISO downloaded from Microsoft. To mount the ISO, double-click on the ISO in Finder.
- Drag all the files and folders from the mounted ISO to the USB flash drive.
- Drag the contents of the Windows Support Software to the USB flash drive.
- If there is not an AutoUnattend.xml at the top level of the drive (as shown below), download AutoUnattend.xml, unzip it, and add it to the drive. AutoUnattend.xml provides the location of the $WinPEDriver$ folder to load the drivers during boot.
- The 2018 MacBook Air (and potentially Macs after that) cannot load the IntelMEI driver and give a 'Windows Setup could not install one or more boot-critical drivers. To install Windows, make sure that the drivers are valid, and restart the installation' message. On the USB flash drive, open the $WinPEDriver$ and remove the IntelMEI folder.
Once the flash drive has been created, it should look like this:
The $WinPEDriver$ folder is important because it contains the drivers for Windows to boot successfully from the USB flash drive and the hardware on that Mac.
Boot from the USB Flash drive
To inject the drivers, the Mac must be booted from the USB flash drive.
- Insert the USB flash drive into an available USB port on the Mac
- Reboot while holding the Option key.
- Select EFI volume in the startup selector.
If Windows does not boot from the USB flash drive after showing the Windows logo, you may have to run the following command to tell the firmware to boot the Windows installer from the USB flash drive. This has been observed on the late-2014 Mac Mini but may affect other models as well. To set the variable:
- Disable SIP by booting to the recovery partition.
- Boot back to macOS and open Terminal. Run the following command and enter the admin password when prompted:
sudo nvram InstallWindowsUEFI=1
Insert the USB flash drive if it is not inserted, reboot, and select the EFI volume from the startup selector.
Note: the InstallWindowsUEFI variable is cleared at each reboot, so you will need to set it again if you do not select the USB Flash Drive.
Command Prompt and Mapped Drives
When Windows 10 starts up, it will prompt for installation of Windows 10. To open a DOS window, press fn-Shift-F10 (or just shift-F10) or click Repair Computer->Troubleshoot->Command Prompt (if available).
Once in the command prompt, there are usually 3 drive letters available: X, C, and D.
- X: This is Windows that you are booted into in memory. The files from the boot.wim on the flash drive are copied to memory and then booted to
- C: Boot Camp partition
- D: The USB Flash drive
Running Utilities
Within the Windows command prompt, you can run utilities on the Boot Camp partition.
Video
Every operating system can crash at one time or another. While it's safe to say that macOS is more stable than Windows, it can still be affected by issues that prevent your computer from booting up. In such cases, you might need to boot your Mac from a USB flash drive to fix the problem. This article shows you two ways to boot Mac from external USB stick, as well as some troubleshooting tips in case Mac won't boot from the target USB.
Boot Mac from USB Option l: Startup Manager
If your Mac won't boot up normally, you can set it to boot from a different drive, such as a USB stick containing macOS installation files in bootable format. The drive will have to contain a version of the OS that is compatible with the Mac. As long as you have the bootable installation USB, you can start your Mac from the USB by accessing the Startup Manager. Here are the steps to be followed:
Step 1: Insert the bootable USB into Mac and power it on.
Step 2: As soon as the startup process begins, hold down the Option (alt) key and keep it depressed until you see the Startup Manager on your screen. If there is a firmware password on your Mac, hold down the Option key until you're asked to enter that password.
Step 3: You will now see the various startup disk options, and your USB will be listed there. If you click on the Up arrow right below the icon for the USB, the computer will only startup once using this disk. Mbr tools. If you press and hold down the Control key while making your selection, it will be saved, and your computer will boot from the USB every time, as long as it is left in the computer.
Boot Macbook From External Drive
At this point, you can also use the Mac installation disk to boot your Mac from. It will appear as EFI Boot, and it works on all computers running macOS 10.9 or higher.
Boot Mac from USB Option 2: Safe Mode/Recovery Mode
As an alternative, you can start your Mac in Safe Mode (Recovery Mode). This will allow the system to automatically detect and repair directory issues. Safe Mode will only allow required kernel extensions to load, preventing login items and startup items to load automatically. It can also help you isolate the issue depending on whether or not the issue goes away in Safe Mode. If the issues you have during normal startup don't show up in safe mode, they are most likely fixed. That means you can reboot normally and your system should be back to normal.
Step 1: Start your Mac and hold down the Shift key. You will see the Apple logo on your screen.
Step 2: When you see the login screen, you can release the Shift key and login to your Mac.
Step 3: To check whether your Mac has booted into Safe Mode, click on the Apple logo on the top left and then on About this Mac. In the window that opens, click on System Report… You should be able to see this:
How to Fix Mac Won't Boot from USB Drive
Sometimes Mac won't boot from USB as expected. If you are unable to select a different startup disk, it's possible that your disk is not showing up in Startup Manager. How to unlock my mac with apple watch. If you try Method 1 above but don't see your USB drive listed there, it could mean one of the following problems:
Compatibility: It is possible that the version of macOS or Mac OS X that you have on the USB drive is not compatible with the hardware. That means you won't be able to see it in the Startup Manager so, of course, you won't be able to boot from it. In such cases, you may need to burn a compatible macOS version on USB drive in order to be able to boot Mac from it.
Startup Security Utility: In certain cases where your Mac has the Apple T2 Security Chip (2018 and later devices), it may be your Startup Security Utility settings that are preventing you from booting from USB. In this situation, restart your Mac and hold down the Command + R keys when you see the Apple logo. How to install downloaded programs on mac. This will put your Mac into Recovery mode. In macOS Utilities, go to Utilities >Startup Security Utility and sign in as admin. Under External Boot, select the second option - Allow Booting from External Media.
Option ROM Firmware: Another known issue is that Option ROM firmware will not load in Startup Manager until you press certain keys manually. To do this, use Method 1 to access Startup Manager. Once you are there, press Option-Shift-Command-Period. You should now be able to see the USB drive. This is not exactly a problem as much as a feature. If the USB contains Option ROM firmware, you will need to press those keys everytime to boot from your pen drive.
Using Flash Drive On Mac
These two methods and the troubleshooting tips should allow you to boot from USB or in Safe Mode so you can then isolate the problem that's preventing your Mac from booting up normally. Free jacks or better video poker games.
