Assuming Vista or 7 (this should work on XP, 8, 8.1, and 10, as well) and that the disk is not showing up under My Computer at all:. Connect your disk. Run cmd as an Administrator. Run diskpart.exe. If you need help in this program. list disk. Find the disk that corresponds to your USB disk.
Depending on the file system you using to format USB stick. Windows can not work with HFS Journaled or AFS (macOS files systems before and after 10.13) without any 3rd party software. MacOS can only mount NTFS volumes To be sure the PC can read it easily, format the USB drive as FAT32. A flash drive is a simple, inexpensive, and portable emergency boot device that can handle OS X or the macOS. Heck, it can even have both operating systems installed, letting you use the emergency USB flash drive to boot any of the Mac's you may have. Even if you don’t use a notebook, you may want to have a bootable USB flash drive on hand.
Select disk n where n is the number of the disk. Confirm that you're using the right disk with detail disk. clean (Warning: This command erases the disk's partition information. Any data on the disk will no longer be accessible.). create partition primary. No size is needed if you want to use the whole disk.
active. Marks the partition as potentially bootable. format fs=fat32 quick. You can choose NTFS or exFAT instead of FAT32 if you want. (Note: Windows 10 limits FAT32 to 4GB. I recommend using exFAT instead, which is essentially a newer version of the same format.).
assign. Assigns the disk a drive letter. exit to quit. If you're still having problems with the disk after trying this, you might try omitting the quick from step 9 to do a full format. That will take a very long time and usually isn't necessary, but may help uncover physical damage to the disk. In some cases you might need to re-initialize the disk.
As above, this will destroy the data on the disk (or, rather, your ability to access it). To do that from diskpart.exe:. list disk.
select disk n. attributes disk clear readonly. This command will unset the read-only flag on the disk. You can see the current attributes with attributes disk or detail disk.
online disk. Sets the device status to online if it's been disabled. convert mbr. Converts the disk to MBR format, which will work just fine for most disks. If you've got a USB disk larger than 2 terabytes, however, you'll want to use convert gpt instead. I'm not sure if the above commands are all identical on older OSs (XP).
Nowadays, when you buy a USB drive, you can use it right out of the box with your Mac. However, unless it’s been designed for use with a Mac, it won’t be formatted using macOS’ preferred file system (either Mac OS Extended or APFS, depending on which version of macOS you’re running). That’s because most of the computers in the world run Windows, and Windows uses a different file system, usually one known as Fat32.
Drives formatted as Fat32 can be read from and written to by macOS, but it’s not optimal and you’re more likely to run into problems than if you use macOS’ native format. So, if you’ve bought a USB drive that’s formatted as Fat32, or any other format other than Mac OS Extended (also known as HFS+) or APFS, here’s how to format a USB drive on Mac. It’s exactly the same procedure if you need to reformat a flash drive on a Mac. How to format a USB drive on a Mac 1. Plug the drive into a USB socket (if you have a recent MacBook or MacBook Pro that only has USB-C connectors, you’ll need a USB-C to USB-A adaptor). Open a new Finder window and click on the drive.
Make sure it has no files on it that you need. The process of reformatting it will wipe all the data from it. Once you’ve copied any files you need from the USB drive to your Mac, go to ApplicationsUtilities and double-click on Disk Utility. Click on the USB drive in the sidebar and then choose Erase from the toolbar at the top of the window. In the window that drops down type a name for the formatted drive in the box next to Name. Choose a format from the dropdown menu. If you have previously stored sensitive data on the drive, click the Security tab.
Choose a security level using the slider. The further to the right you move the slider, the more ‘passes’ the erase tool will make and the more securely files will be deleted. However, it also increases the time it takes to format the drive quite considerably. Click Ok then click Erase. Tip: You don’t need to erase a whole drive to delete files securely.
If you have confidential files or sensitive data you need to remove from your Mac completely, you should use File Shredder. It’s specifically designed to securely delete sensitive data and will render it unrecoverable. You can download CleanMyMac X for free. Which format to choose? If your Mac is running macOS High Sierra or later, you have two options for file formats: APFS and Mac OS Extended.
Which should you choose? The key point is that disks formatted as APFS won’t be recognized by Macs running versions of macOS older than High Sierra. So if you think you might need to plug the USB drive into a Mac running an older version of macOS, format it as Mac OS Extended. APFS is optimized for SSD (solid state drive) such as flash drives, so if you reformat a flash drive on a Mac, you should definitely choose APFS (unless you plan to use it with a pre-High Sierra Mac, of course). Even on hard drives, however, APFS is faster and more reliable than Mac OS Extended. Finally, if you plan to use the USB drive as a destination for Time Machine backups, choose Mac OS Extended.
Time Machine can’t currently back up to an APFS disk and if you select one for use with Time Machine, it will offer to reformat it as Mac OS Extended. You can, however, backup an APFS formatted disk to a Mac OS Extended Time Machine drive. How to format a USB drive to FAT32 on a Mac The main reason for formatting a USB drive as Fat32 on a Mac is that you want to be able to use the drive on a Windows PC, as well as a Mac — perhaps to transfer files between the two machines. You may also be preparing the drive for use as, say, a storage device for a media player or to record TV programmes on a TV with a USB port. The fact that Fat32 can be read from and written to on both Mac and Windows makes it very versatile. However, there is a significant limitation — individual files have a maximum size of 4GB.
So, if you’re using the USB drive to store large video files, you may run into trouble. There is a solution, however, exFAT. Unlike FAT32, exFAT doesn’t have a maximum file limit. Better still, it can be read from and written to on any Mac running Mac OS X Snow Leopard or later and on Windows. To format a USB drive in FAT32 or exFAT: 1. Plug the USB drive into your Mac.
Go to ApplicationsUtilities and launch Disk Utility. Click on the USB drive in the sidebar in Disk Utility. Click Erase in the Disk Utility toolbar. Type in a name for the formatted disk. Click on the Format menu and choose either MS-DOS (FAT32) or ExFAT. Your USB drive will now be erased and re-formatted as either FAT32 or ExFAT, depending on the format you chose in step 6.
How to manage your drives easily If you look for a quick and easy way to manage your drives, try using. With its help, you can drag-and-drop files directly to any drive, clean hidden junk from external drives, and check disk stats. It works for all drives, including USB drives, SSD, SD cards, external hard drives. All the drives will be at hand in the menu bar, so you can get to see types of drives you have and manage them easily. CleanMyDrive is absolutely free to use, so download it on the Mac App Store and enjoy! It’s very easy to format a USB drive on a Mac using Disk Utility. There are a couple of things you should keep in mind, however.
The first is that when you format and disk, you will erase all the data currently on it. So if you need that data, make sure you copy it onto another disk before you start. Secondly, there are several formats to choose from, each with advantages and disadvantage. Use the guide above to help you decide which is right for you. These might also interest you:.