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extreme · May 11, 2006, 09:13 PM

Hi there,
I have an external firewire hard disk formatted in Mac OS X Tiger file system. Today, I had to transfer some data from my ibook to my friend's pc. i used my external drive for this. But when I plugged in my drive to the windows computer, the disk didn't show up. I thought it should show up because windows-formatted disks usually show up on my mac. So i checked in the windows disk manager. It said i had to initialize the disk for use on windows. so i did this and it took it a second or so to initialize it.. But now my disk shows as unformatted in windows and it doesn't show up in mac os x. I want to recover my data. Please help.

icruise · May 12, 2006, 12:27 AM

Mac OS X can read Windows disks, but Windows can't read Mac-formatted disks without special software like MacDrive.

extreme · May 12, 2006, 01:42 AM

Ohh... thats why windows didnt read the disk... but what about the data now?

icruise · May 12, 2006, 04:07 AM

Sorry, I missed that part. Initializing the disk is the same thing as formatting (erasing) it. Depending on how you did the format and whether you've written data to the disk since doing it, you may still be able to recover the data. You will need to look for a program that can unerase a formatted disk. I don't know offhand what is best for that. In any case, don't write anything to the disk or you run the risk of erasing your data.

Dr.Michael · May 12, 2006, 05:57 AM

Originally Posted by extreme

Ohh... thats why windows didnt read the disk... but what about the data now?

Now you know what initializing a disk means.
There is no easy way to recover the data. But you have written, that you have the data on your ibook? So this may not be a problem.

Take the disk again to your friends computer and format it as Fat32 (this destroys everything that is on that disk). Then both your Mac and his PC have read and write access in the future.

monkeybrain · 08:06 AM

I was gonna start a separate thread for this, but may as well ask it here since it may help the original poster too.

Does formatting a disk to FAT32 have any disadvantages for the Mac? The one that comes to mind is: can Spotlight index and search it?

Also, can Disk Utility create FAT32 disks?

monkeybrain · May 12, 2006, 08:05 AM

Double post.

icruise · May 13, 2006, 01:43 AM

Originally Posted by monkeybrain

I was gonna start a separate thread for this, but may as well ask it here since it may help the original poster too.

Does formatting a disk to FAT32 have any disadvantages for the Mac? The one that comes to mind is: can Spotlight index and search it?

Also, can Disk Utility create FAT32 disks?

Spotlight can search a FAT32 disk, and you can read and write to it. Not sure about whether Disk Utility can create one. But I believe that FAT32 doesn't allow some file names that the Mac format does, which might cause problems in some cases. And of course, you can't install the Mac OS onto a FAT32-formatted disk.

tooki · May 14, 2006, 04:20 PM

On a Mac it's slower, and FAT32 suffers from much more fragmentation than HFS+, and it doesn't support metadata like file permissions, etc.

In other words, if you can, avoid using it.

tooki

FireWire · May 16, 2006, 10:15 AM

Originally Posted by monkeybrain

Also, can Disk Utility create FAT32 disks?

I was wondering the same thing too. I have an external HD splitted in two partitions. I'd like to use one for file transfer with some PC, but I can't find the appropriate format (MS-DOS or FAT32) in disk utility (and to my great surprise, there's no Erase... option in the Finder anymore

) When I select the volume in Disk Utility, I have either HFS+ (and its different flavors) or UNIX.. When I select the disk, however, I have the MS-DOS option.

This may sound like a stupid question, but is there a (free) way to format a volume in FAT32 (or at least MS-DOS) in Mac OS X? I'm a little bit deceived by Apple on this one, one more thing that was easier in OS 9..

tooki · May 16, 2006, 12:38 PM

No, what you're seeing is that Disk Utility will not let you format just a partition as FAT. The whole disk, or nothing. It can be done, if you google around, though.

tooki

FireWire · May 16, 2006, 09:26 PM

Originally Posted by tooki

No, what you're seeing is that Disk Utility will not let you format just a partition as FAT. The whole disk, or nothing. It can be done, if you google around, though.

As a matter of fact, I did Google and search the forum before posting, but found nothing useful. It seems most people had these options included in Disk Utility or you had to issue "risky" Terminal command, which I'm wary of when we're talking about formatting a hard drive, whose other partition contains important data...

I said alea jacta est to myself and I tried to use diskutil, but the list of filesystems available didn't seem to include FAT32:

Code:
[MyComputer:/system/library/filesystems] myself% ls
AppleShare      cd9660.fs       hfs.fs          ntfs.fs         ufs.fs
URLMount        cddafs.fs       msdos.fs        smbfs.fs        webdav.fs
afpfs.fs        ftp.fs          nfs.fs          udf.fs

(Well, now that I think about it, it was probably smbfs, D'oh!)*

I subsquently tried the command "newfs_msdos -v DISKPC -F32 /dev/rdisk2s3" (with the correct volume name). It seemed to work:

Code:
/dev/rdisk2s3: 194068416 sectors in 3032319 FAT32 clusters (32768 bytes/cluster)
bps=512 spc=64 res=32 nft=2 mid=0xf0 spt=32 hds=255 hid=0 bsec=194115848 bspf=23691 rdcl=2 infs=1 bkbs=6

but it didn't mount and DU still reported it as being in HFS+...

*now I'm tempted to use diskutil again, but the example in the man pages refer to HFS+ (diskutil eraseVolume HFS+ UntitledHFS /Volumes/SomeDisk), and this name is not in the list they tell to consult, so I cannot just use smbfs.fs and I don't want to guess commands in the terminal...

Finally... as I was about to give up, I stumbled accros a post which suggested using "sudo diskutil eraseVolume "MS-DOS FAT32" DISKPC /Volumes/DISKPC
" which worked after a few more steps. I had to try this command without sudo before diskutil finally spitted its format options, it's about time...

Code:
Valid filesystems: "Case-sensitive HFS+" "Journaled HFS+" "Case-sensitive Journaled HFS+" "HFS+" "HFS" "MS-DOS FAT32" "MS-DOS FAT16" "MS-DOS" "MS-DOS FAT12" "UFS" "Linux" "Swap"

Would it be that difficult to put that option in the GUI somewhere? (or at least in the man pages, for the dare-devil)

Apple! What have you done!?