WARNING: Formatting will erase all data on the device. Back up all your data before proceeding.
Instructions below are for 10.11.x (El Capitan) and 10.12.x (Sierra)
The overwhelming majority of USB flash drives you buy are going to come in one of two formats: FAT32 or NTFS. The first format, FAT32, is fully compatible with Mac OS X, though with some drawbacks.
1. Double-click on Macintosh HD - or in the Finder menu clickFile > New Finder Window
2. Click the Applications folder - if using a Finder Window Applicationswill be in the left side menu.
3. Click the Utilities folder.
4. Double-click Disk Utility.
5. On the left side of the window are the drives connected to the computer. Select the capacity of the drive respective to the one containing the device you wish to format then click the Erase tab.
Example: If the drive is called 'NO NAME', directly above that, you should see the drive capacity of 'XXXX'. Select this capacity.
6. Verify Volume Format is set to MS-DOS file system or exFAT, Scheme is set to “Master Boot Record” (Do NOT select GUID Partition Map) then click Erase.
Instructions below are for 10.13.x (High Sierra)
1. Open Disk Utility. Please See Answer 20985: How to access Disk Utility macOS
2. In the top menu bar, go to View, and choose Show All Devices
3. Select the upper level of the drive you would like to format and click the Erase button
Click “Disk Utility” to open it, and click on the name of the flash drive in the sidebar. Click on the “Erase” tab at the top of the window. Select the format for your flash drive. In the drop-down list next to “Format”, select the format that you want to use for the flash drive. You can also set a name for your drive. Follow the below steps in order to create a bootable macOS Catalina USB Drive. Format your USB Drive:. Connect your USB drive to the USB port of your computer. Press Command+ Space to launch spotlight, type in ‘Disk Utility,” and press the return to launch the app. It will take a while for Catalina to be written to the flash drive as a bootable installer. Once done, restart the Mac and immediately hold down the Option key. Choose the flash drive as the startup volume. When it gets to the work screen, run Disk Utility from the top menu bar. Choose to convert the main drive to APFS.
Mac Catalina Iso
4. Choose how you would like to format the drive
- Enter a Name for your drive
- Choose exFAT or MS-DOS (FAT) for the format
- Choose Master Boot Record for the Scheme
- Click Erase
5. When finished, the drive will be formatted and repartitioned successfully. Click the Done button
NOTE: exFAT is used on SDXC card (64GB and higher).
NOTE: exFAT can be used on flash drives or memory cards to transfer files larger than 4GB.
NOTE: MacOS 10.6.2 or higher is required for exFAT file system. Some older operating systems must have a patch installed before they can use the exFAT file system.
NOTE: If the above steps do NOT resolve the problem or if the lock switch is missing or broken, please back up your data and request a replacement using our online web form.
Format Flash Drive Mac Catalina Island
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