This article was first published on 2008-01-31. Due to the age of this article, it is included here for archive purposes only.


 

So you have a PC, a Mac and an external hard drive you want to all play friendly. Well it’s not as easy as it sounds.

 

Sure, the USB or Firewire ports are the same on both machines, but the real culprit is file formats.

 

Windows uses either FAT32 or NTFS. Mac OS X uses Mac OS Extended also known as HFS+. All you really need to know is that they are just three different methods for storing information. Macs can handle some Windows formats, but Windows cannot handle HFS+ without additional software.

 

To see the format of the external drive, right-click on the icon and select Properties (Windows) or Get Info (Mac)

 

Mac OS X has been able to read and write FAT32 formatted hard drives since the very beginning. If you have a FAT32 drive you can simply connect it to your Mac and it will very easily be able to read and write to it. There is nothing special you need to do. However, there are two limitations of FAT32. 1.) It only supports file sizes of 4GB or less. 2.) Some Mac applications may not run from the drive as FAT32 does not adequately handle the permissions structure of Mac OS X.

 

NTFS is a different story. NTFS is a more modern Windows format but is proprietary to Microsoft. Licensing is required to use it which is probably why Apple doesn’t fully support it. Macs can read an NTFS drive, but they cannot write to one. So you have 4 options if you have an NTFS external hard drive:

Option Pro Cons
Leave NTFS if you are just using the drive to transfer files from the PC to the Mac. Easy – Nothing to do. You will not be able to transfer files from the Mac to the PC.
Reformat your NTFS drive to FAT32. Don’t forget to backup your files first!

Easy

Requires no special software

Good if you will be sharing the drive equally between the Mac and PC.

You need to reformat the drive.

Limited to 4GB files or less.

Some Mac applications my not run from the drive (not an issue if you are simply backing up though).

Reformat your drive to HFS+. You will need software such as MacDrive ($50) so that Windows will be able to read/write to the drive. Good if you think you will primarily use the drive on the Mac and only occasionally on the PC.

Cost

Relatively more complicated to install/maintain.

Keep NTFS and install NTFS For Mac 6.0 ($30) so that the Mac will be able to read and write to the drive. Good if you will be using the drive primarily on the PC.

Cost

Relatively more complicated to install/maintain.

 

How to Format Your External Hard Drive – Mac OS X

  • Backup any data on the drive – formatting will erase everything.
  • Open “Disk Utility” (Applications/Utilities/Disk Utility)
  • Click on the External Drive
  • Click on the “Erase” tab
  • In “Volume Format” select either Mac OS Extended (Journaled) or MS-DOS (FAT32).
  • Click “Erase”


    Note: This is to format your drive using the default settings. You can further customize the formatting by selecting partitions, security settings, free space and other options. See http://www.kenstone.net/fcp_homepage/partitioning_tiger.html for a great step-by-step walkthrough.

    How to Format Your External Hard Drive – Windows

  • Backup any data on the drive – formatting will erase everything.
  • Double-click on “My Computer”
  • Right-click on the External Drive
  • Select “Format…”
  • In “File System” select either FAT32 or NTFS
  • Click “Start”

    Note: This is to format your drive using the default settings. You can further customize the formatting by selecting capacity, allocation size and other options. See http://support.microsoft.com/kb/313348 for further details.

Do you have any tips to share about using your HD on both a Mac and PC? Let us know or ask questions in the Comments section below!