Formatting External Drive for FAT32

This morning I decided to backup my work PC (Windows), which I haven't done for a long time. I took out my trusty old Buslink 80 GB USB2.0 drive and plugged it into my PC, totally forgetting that I had reformatted that drive to HFS+ (the Mac disk format). Windows beeped at me, indicating that it recognized that I had plugged something in (Windows is SO helpful, isn't it? <grin>) but that was all. The drive didn't show up in My Computer, nor anywhere else except the Safely Eject Hardware item in the system tray.

After a moment of head scratching, I realized what had to be wrong and plugged the drive into my Mac, thinking to reformat it to FAT32 on the Mac, which is MUCH more helpful generally. The drive immediately showed up on my desktop (thank you Apple!). I ejected it, started Disk Utility and selected Erase. To my great surprise, there was no option for FAT32, Windows, or any other formats except variations of HFS and Unix format. Not so helpful after all!

A little Googling later, I came up on this gem, which details the Terminal comands needed to reformat a disk with FAT32. This has worked like a champ, and I thought I would pass it on to this community, lest it help anyone else wondering about this problem.

http://www.macosxhints.com/article.php?story=20030613121738812

A bit obscure, but it worked very well. I find it ironic that I had to use my Mac to format a drive for use in Windows - Windows wouldn't allow me to accomplish this feat by itself! Windows is SO helpful, isn't it? :dummy:

The magic command, lest the above URL should disappear in the future:

In Terminal, type:

newfs_msdos -V volume_name -F 32 /dev/rdisk2

Note that this command may take a minute or two to execute, and provides no feedback while it is doing it's job. That last name (/dev/rdisk2) can be determined by issuing the command:

ls /dev/rdisk?

before and after plugging in the drive. You will see an additional entry in the listing after you have plugged the drive in vs. before. That new entry is the name to use in the newfs_msdos command.

So I thought I would tell you that MS-DOS is FAT-32

A better way is to select the drive, rather than the volume, and select the partitioning tool. Select one partition with MS-DOS filesystem and let it do its stuff. There appears to be a better selection of filesystems that way due to the various supported partitioning schemes.

Handy to know the command line way to do it though

IronMac, I wish it was that simple. It wasn't. Remember, this was a HFS+ drive that I wanted to format, so there was no pre existing MS-DOS partition for it to show. Under the available formats, Disk Utility did not offer me the option of MS-DOS, Windows, FAT32 or *anything* except variations of HFS and of course, unix file system (does *anybody* use this any more?).

Of course now that it is formatted, I suspect that it would show up as an option in Disk Utility at this point. Anyway, I was glad that a command line way existed, and have tucked away an application note to myself for the future.

Question regarding this thread..

Interesting stuff. I hope that someone might be able to answer my question, since it's related. I see this thread was up a while ago.

My harddrive was formatted in MS-Dos, however my Macbook couldn't do anything with it. I got error messages when I tried to write to it. Since you say that MS-Dos is FAT32 and I keep reading that FAT32 is read/writable from a Mac, does anyone know why I couldn't write to it?

On another forum, I was told that maybe the harddrive had something called NTFS which Mac can't write to... How are NTFS, HFS+ and FAT32 related then? I followed prompts to format into HFS+ (being a newb, I thought this was a good idea) and was appalled when I realized that now my pc (stupid heavy bookend) wouldn't recognize the harddrive. I installed macdrive on my pc and now my harddrive works everywhere, but I won't be able to use the harddrive with other pcs (family and friends and such)...

I have 89GB saved on it already so when I get access to another harddrive to transfer that to, I was thinking of reformatting my harddrive to FAT32 (or MS-Dos) but I'm not so sure now that it will work at all, as my mac didn't recognize it before...

Help?

You have to recreate the partition table to format it as MS-DOS. So IronMac was correct.

Sorry to hear you did things the long way ;P

Kash said:

You have to recreate the partition table

Click to expand...

Okay, do you mean simply that I should go back into disk utility for my harddrive and change the format to MS-Dos again and it should now work, regardless of the fact that it didn't work before?

I can do that, but would it work?