By default, Mac starts from its built-in hard disk, but a startup disk can be any storage device that contains bootable contents that compatible with your Mac. For example, if you install macOS or Microsoft Windows on a USB drive, your Mac can recognize that drive as a startup disk. This guide provides 2 ways to boot a Mac from a USB flash drive.
Choose your format, probably exFAT if you want to make sure it's compatible with PC and Mac, otherwise, Mac OS Extended (Journaled) is probably the best option. Give the drive a name. NO.1 USB drive formatting software for Mac – DoYourData Super Eraser. DoYourData Super Eraser.
Requirement
Starting up your Mac from an external disk requires the following:
- Intel-based Mac.
- Bootable USB thumb drive formatted with a GUID partition type and containing an OS X installer or a usable operating system.
Let’s see how to boot a Mac from a bootable USB drive and what to do if your Mac doesn’t start up from it.
Way 1: Boot Mac from USB Drive using Startup Manager
Getting your Mac to load from a USB drive is fairly straightforward. Use the following steps, you can easily set Mac boot from an external drive in Startup Manager, so it’ll only boot from USB that one time.
Step 1: Insert the USB boot media into a USB slot.
Step 2: Turn on your Mac (or Restart your Mac if it’s already on).
Step 3: Press and hold the Option key immediately after you see the Apple logo. Holding that key gives you access to OS X’s Startup Manager. Once the Startup Manager screen appears, release the Option key. The utility will look for any available drives that include bootable content.
Step 4: Using either the pointer or arrow keys on the keyboard, select the USB drive you wish to boot from. Once selected, either hit the Return key or double-click your selection. The machine will start to boot from the USB drive.
Way 2: Set a Mac Boot from USB Drive using Startup Disk
Format Thumb Drive Mac Os
When you use Startup Disk preferences to set Mac boot from an external drive, so it’ll boot from that disk until you choose a different one. Here is how:
Step 1: Go to Apple menu > System Preference, then click Startup Disk.
Step 2: Click the locked icon and then enter your administrator password.
Step 3: Select External drive as the startup disk, then restart your Mac.
What to do if your Mac does not boot from the selected drive
If you see a message prompts that your security settings do not allow this Mac to use an external startup disk, check the External Boot setting in Startup Security Utility, and then allow your Mac to use an external startup disk.
Step 1: Open Startup Security Utility.
Turn on your Mac, then press and hold Command (⌘) + R immediately after you see the Apple logo. Your Mac starts up from macOS Recovery. When you see the macOS utility window, choose Utilities > Startup Security Utility from the menu bar. When you’re asked to authenticate, click Enter macOS Password, then choose an administrator account and enter its password.
Step 2: Select “Allow booting from external media“.
If you want to select an external startup disk before restarting your Mac, quit Startup Security Utility, then choose Apple menu > Startup Disk.
Note: If you’re using Boot Camp in a dual-boot Windows/OS X environment, you may be unable to boot negatively into supported versions of Microsoft Windows XP, Windows Vista or Windows 10 operating systems installed on external USB hard drive.
Make sure disk has been formatted with a GUID partition type
Intel-based Macs support starting from an external USB storage device’s volume that has been formatted with a GUID partition type. If you wish to boot from the drive, it’s important to format the partition as “GUID Partition Table” rather than either of the other two ahead of time when you use that drive as a bootable drive.
Make sure your disk is bootable
Volumes that aren’t bootable and don’t contain a copy of a valid operating system aren’t listed in Startup Disk or Startup Manager. Make sure the external drive you’re trying to start from contains a usable operating system.
You can format the external hard drive or USB drive to make it compatible with both Mac and Windows machines. This thing is still unknown for many users but doesn’t worry it’s not complex.
If you are tech savvy and use Windows and Mac computers frequently, then you might need to transfer data between Mac and PC. Windows and macOS filesystems are different and you might need to format the drive every time to use on both platforms. You don’t need to format the hard drive every time you can choose a filesystem while formatting the drive so the hard drive or USB drive work on both Mac and PC
So to get rid of these situations we bring here a guide that will help you to format your drive which works on both platforms and you don’t need to format and backup data every time. After cross-compatible formatting, simply unplug the drive from one machine and then plug it into another. Sounds good to you right? So let’s started, how this works.
Understand file systems for Mac and Windows
There are three common file system types to format an external USB or hard drive, SSD drive, SD card and etc. FAT32, NTFS, and exFAT let’s have a look what’s the difference between these formats.
FAT 32 Format
This format is pretty old but supported and it’s not efficient as compared to NTFS. It doesn’t support big features but offers great compatibility which means it’s compatible with all versions of Windows. It can only support 4GB file size and up to 8TB hard drivers. It’s not capable to store files larger than 4GB.
NTFS Format
NTFS is a modern format system and Windows also uses this format for itself and for other non-removable drives by default. This format is also compatible with all versions of Windows but limited to none Windows OS as FAT32.
exFAT Format
exFAT drives are faster at reading and writing as compared to FAT32. This format can store large files and it’s also lightweight. It’s compatible with all versions of Windows and the best thing it’s along with Windows it’s also compatible with macOS, Linux, and Android, etc.
- If your drive is formatted as Windows default format NTFS then it’s only readable to macOS. You can’t do more than that or you have to install a separate app on Mac to read write the drive.
- Drive with macOS format HFS+ cant readable to Windows.
- FAT32 format works on both Windows and Mac but the problem is you can only work with files with a maximum size of 4GB.
Learn more: Copy data on NTFS drive in macOS
FAT32 is much better than NTFS and HFS+ becuase it works on both operating systems. You can also install drivers on each OS to make work your drive. So exFAT is much better than all of these formats and a simple option but this will not work on Leopard.
Format a USB Drive on Mac
Time needed: 5 minutes.
First, let’s see how to format an external hard drive or USB drive in macOS which works with both Mac and PC platforms, first plug-in your drive into a macOS machine.
- Disk Utility
Open Disk Utility on your macOS, press
cmd + spacebarkeys, and type Disk Utility in the spotlight search. Open Disk Utility from the search results. - Erase Drive
On the Disk Utility interface, select an external drive click on the Erase button from the top of the window (make sure and backup your drive before erasing it).
- Drive format
Now enter the name for the external drive which will be used after formatting and also select the exFAT for Format option and click on the Erase. This will format the drive as exFAT format and your drive is now compatible with both platforms.
Format USB Drive in Windows
The below steps for formatting external drive is for Windows 10 and also works the same with an old version of Windows. To format your external drive hard drive in Windows to use on Mac and PC platforms, first plug-in your drive with a Windows machine.
Open the Disk Management tool by right-clicking on the start menu icon and then select Disk Management. Now right click on the external drive and click on the format option (double-check the drive name and capacity to make sure you are going to format the right drive.)
Now enter the Volume label as you need and change the File system for exFat and click OK. Now you are done.
Format Thumb Drive Mac Os Xp
Share your experience, how do you use an external hard drive on both Mac and PC. Did you format the drive as exFAT ? or use any utility that helps the system to read another type of file system. Please leave a comment below.