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external hard drive with mac

How To Format An External Hard Drive For Both Mac & PC Use

There often comes an annoying dilemma when buying or using an external hard drive that is the lack of compatibility between the Windows and Mac operating system. For example in my recent review of the Western Digital My Passport, I stated how the device was available in a $150 Windows version and a $160 Mac version. In order to take advantage of accessibility to both operating systems and save $10 I decided to reformat the hard drive myself.

Step 1 – Be sure to backup any important files on your external hard drive

Assuming that your device is not brand new out of the box like mine was, you will need to be sure to back up your hard drive's contents before performing the reformat. If your perform the reformat without doing this step you will lose all files that you previously had on the device and they will likely be unrecoverable. The best way to do this backup is save to all the contents on your computer's hard drive then reformat the device and re-transfer all your contents back onto the external hard drive.

Step 2 – Open Disk Utility

In order to be able to read/write any size file on both Mac and Windows you want to format the hard drive you want to open the application “Disk Utility” on your Mac computer. Make sure your device is plugged in and showing up on the left column like you see below.

Screen Shot 2013-02-04 at 2.11.22 PM

Step 3: Go under “Erase” and choose format “ExFat”

By choosing ExFat you will be able to read and write from both a Mac and Windows operating system. You also will not have a 4GB file cape like you with with NTFS. You should also name your device at this step to whatever you desire before moving forward as you can see above I called mine “Colt's 2TB”.

Step 4: Click “Erase” and wait for the reformat to complete.

Once you initiate the reformat it should not take very long and will likely finish in less than a minute. It is very important that you don't turn off or unplug the drive during this period and let it finish completely.

Step 5: Unplug and enjoy your Windows & Mac compatible external hard drive!

Once the process is complete follow the instructions and unplug your device if not in use and your good to go! You can now transfer, read, and write any size files to your hard drive no matter whether it is from a Mac or Windows operating system.

Photo Credit: Mike LaPlante