Sharing an External Drive Between a PC and a Mac, exFAT Discussion, Results

I bought a new external 500GB USB drive for my laptop, which happens to be a Mac that I also run Windows 7 in a Virtual Machine. I wanted to be able to use this external drive on my Mac to store files such as larger Virtual Machine’s, software, etc while at the same time keeping the ability to be able to read this drive from a Windows machine without installing any software on the Windows machine. This lesson shows how exFAT as well as other format types stacked up for this purpose and what my final result was.

Why this Post?

I began to Google for my solution which brought up a ton of forum and blog posts that had different ideas. Thus the reason for this lesson so that someone might benefit from what I tried, as I know the ideas and things tried by others that I found were useful to me.

Why Not Use NTFS?

I’m currently running Snow Leopard 10.6.1 which can read NTFS volumes but not write to them natively. So I started to investigate other file system types to see what might work the best.

Why Not Use FAT32?

The USB drive that I bought actually came preformatted with a FAT32 file system. I thought this might work great, however I started copying a 10GB Viirtual Machine file to the drive and it immediently failed with an error. A quick search turned up something which I haven’t had to deal with in a long time… FAT32 filesystem has a 4GB file size limitation. So, that definately won’t work for what I’m trying to do as I have a ton of files (VM files, ISO’s, etc) that are larger than 4GB.

What about exFAT?

I stumbled across the new exFAT file system (also referred by some as FAT64) in some blogs when searching how to share an external drive between a Mac and PC. It sounded like the possible answer. exFAT is a newer file system that can be used by the newer versions of Windows (e.g. my Windows 7 VM) but the question remained, can Snow Leopard read the exFAT file system with out a lot of work? A lot of blogs didn’t think so but none that I found actually tried it. So, let’s give it a shot!

New Blank Drive


Here’s my new blank drive ready to be formatted with whatever filesystem I’d like. Let’s try exFAT.


Here are my options under Windows 7. Since I only have 1 disk, I can only choose “New Simple Volume”.


Beginning the New Simple Volume Wizard.


Choosing the volume size, which we’ll allocate the full space.


Assigning the drive letter. In this example, we’ll use “E”.


Choosing the exFAT File System type.


Changing the volume label so I can identify the drive.


Summary screen for the new exFAT file system.

exFAT in Disk Manager


Here’s the newly formatted volume in Disk Management. Everything looks good so far.

exFAT Drive – AutoPlay Options


Here are the autoplay options when I plugged the newly formatted exFAT drive in. Notice you can use this new filesystem for backup and for ReadyBoost, just like a NTFS volume can.

Connecting exFAT Drive to a Snow Leopard Mac


I think this screenshot says it all. The Mac didn’t know what to do with this drive and wanted me to “initialize” it — which would erase everything on the drive if I proceeded with that option. I selected “ignore” and that’s basically where trying to use a exFAT drive on a Mac stops. I searched numerous forum posts and blogs and there just isn’t a good solution yet. Perhaps sometime in the future, I’m sure we’ll be able to use exFAT.

What was the final solution?


Since I really wanted the ability to use my drive on a Windows machine, I went back to NTFS. It’s a great filesystem and I figured if I could get my Mac to beable to read and write a NTFS filesystem, that would work great. I ran across basically 2 solutions that you can use for this.

#1 – Paragon NTFS for Mac OS X
Paragon looked like it would work great so I downloaded and installed the trial version off their website. Performance seemed good. I was able to now read and write to my NTFS formatted external drives. At only $19.95 (Fall Special right now), it didn’t seem like that bad of an option. Yet, I ran across the other solution on a blog, which is free. So let’s examine that one.

#2 – NTFS-3G for Mac OS X
NTFS-3G was referred as a Paragon alternative without the cost. So this got me interested. I removed Paragon from the system and installed NTFS-3G. After a reboot, I was able to read/write to my NTFS drives, and without paying anything. Performance in my very simple file transfer tests seemed right on with Paragon’s test results. I copied over 85GB of data to my brand new 500GB external drive, which is formatted with NTFS and everything seems to be working like a champ. I’ve also taken the drive and presented it to my Windows 7 machine and it worked great on there too. The only “gotcha” that I’ve ran across so far is that you need to “Safely Eject this Hardware” from within Windows or you’ll get a complaint by NTFS-3G about data integrity. I’ve usually tried to always remove external drives with that method, so that doesn’t really change anything for me.
The direct link for the free version of NTFS-3G is down on his blog a little bit. It looks like they are releasing a paid version called Tuxera NTFS, but NTFS-3G is still available. As of this writing, the latest version is NTFS-3G 2009.4.4, found here:

28 thoughts on “Sharing an External Drive Between a PC and a Mac, exFAT Discussion, Results

  1. Awesome..! You did EXACTLY what I would have done and just saved me some HOURS of time. Thanks so much my friend. I will go the NTFS route. Thanks for the links.

  2. My compliments on your post – very cleanly done with the screen shots and all. Although I already knew about and use NTFS-3G, I was looking for answers as to whether 10.6 would work with exfat or not – thanks for saving me the time of doing this myself!

  3. I just bought a external drive too, and formatted it as a ExFAT drive directly from my iMac (Mid 2010). And it works great on the Mac. I have still to try connecting it to a PC and then back to the Mac again, but since i formatted it with the iMac, i think it should be ok?

  4. Yea I had the same problem. I had all my photos, kids, me, my work ( I am a photographer) on a hard drive I put from my pc to my mac. All was well till one day it stopped working in either. Now neither pc nor mac will can see it and my data is trapped there till I can figure out what to do. I have use data recovery programs but it does not work. Darn Windows! 🙂

  5. Piece to All mens on the Earth! )))
    Do You Know Snow Leopard 10.6.4 and early cannot work with exFAT volumes?! – start to this only in new MacOSX update (10.6.5)!!! Try again!
    P.S. In my experiments with exFAT on MacOSX I do not understand some trouble with sharing exFAT volumes between 2 MacBook (WiFi-Home Network). Shared HFS+ volumes is visible, exFAT – not! All volumes is in WD My Passport (Q-ty volumes – 3 (HFS Boot, HFS+, exFAT), Master Boot Record in HFS+). Anybody try something like this?

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  7. My son-in-law’s iMac with 10.6.6 will read files on a 2 TB exFAT external HDD formatted under Windows but Time Machine says the drive needs to be formatted for its use.

    Out of curiosity, I may try writing a file or two to the 2 TB drive with the iMac but I don’t want to jeopardize the 270 GB of songs etc, that were recently written to the 2 TB drive.

    I’m going to recommend to my son-in-law that he keep this drive for Windows use and spring for a different drive for this iMac. Talk us out of it if you like. 🙂 Thanks.


  8. exfat was only added to OS X in 10.6.4 and above. You were running 10.6.1. Of course it wont work as it was never supported so why write this article in the first place?

    I have formatted a backup drive in Disk Utility as exfat as well as on Win 7 with no issues.

    Time Machine will not use exfat however as it needs to use HFS+ and will prompt you to reformat the drive to what it needs

  9. Thanks all for the updates. I’ll have to retry my tests with OS X 10.6.4 or greater (especially now that 10.6.6 is out).

    @Kellan – I was running 10.6.1 since in October 2009 when I wrote the article, that was the latest at the time.. 😉

  10. Running 10.6.6 Snow Leopard and formatted partition in OSX using ExFAT for a 90GB partition. Copied files from OSX to verifiy copy. Booted in Windows 7 and copied entire music library to new shared partition. Booted into Snow Leopard and currently importing to ITunes.

    Looks like it works great – at least if you create teh partition in MAC OS.

  11. Hi, I had the same problem, yesterday I did this: I’m running Mac os x on a MacBook Pro 10.6.7 Snow Leopard, and Windows 7 ultimate 64bit. I used to deal with the NTFS format but as you said you can’t write data to the disk on Mac os X. Yesterday I formatted the hard drive with the ExFat option but not via windows, instead directly with the os x disk utility, now I can perfectly read and write data on both operating systems no matter files size. That solved all my problems.

  12. @ Mat, I got a 2.5TB external hard drive and i want to use it on both my iMac and my husbands pc (windows 7). It was not formatted for my Mac so i formatted it with ExFat and it works great with my Mac but when i connect it to the pc, it doesn’t recognize it at all… so I wonder what you did. I followed this link:,219,289/c/123/session/L3RpbWUvMTMwOTcxNzcyOS9zaWQvSE1tVlIzeWs%3D , but chose exFat instead. The only thing with this was that in step 4 it says to choose Master Boot Record but they have selected Apple Partition Map. I used the second and that might have been why it’s not working…
    But I don’t know, anybody able to help me?

  13. I do appreciate the effort that went into this, as I have done similar things. However, if the title had been “Sharing an External Drive Between a PC and a Mac, NOT with exFAT”, it would have saved me a lot of time.

  14. exFAT support has been added as of Mac OS X 10.6.5. I use a single partition exFAT formatted 500GB external HD as a perfect combo storage on my MBP w/ Win7 and MacOS.


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