If you have lots of files—or just a really big one—that you need to share with a Windows user, you may be better off sharing an entire drive instead.
Problem: You want to open Windows-formatted disks on your Mac.
Solution: No problem! (Well, almost.)
As of version 10.3 (Panther), OS X can read any hard drives formatted on a PC, as well as any CDs and DVDs. That includes drives that use the FAT (File Allocation Table) and Windows NTFS (New Technology File System) formats.
However, you have to watch out for a couple of annoying problems with the NTFS format. If you have an NTFS drive connected to your Mac at startup, Mac OS X will ask if you want to format it. Don’t do so unless you want to erase everything on the drive.
Even worse, OS X can’t write to NTFS disks; it can only read them. The only way to write to an NTFS drive from your Mac is to run Windows on the Mac (using Boot Camp or a Windows emulator; see “Running Windows on Your Mac” on the next page). You’ll have complete access to NTFS from within Windows. On PowerPC Macs, some Windows emulators (including Virtual PC) can also write to an NTFS disk image.
Problem: You want to send a disk to a Windows user.
Solution: Format it in FAT32.
Windows cannot read the Mac OS-only HFS (Hierarchical File System) and HFS+ formats. One workaround is to reformat the drive you’re sending. In Disk Utility, go to the Erase tab’s Volume Format pop-up menu and select a format. The best choice here is MS-DOS File System (the PC’s FAT32 format). Just don’t use Mac OS Extended or any of its variations; that’s HFS+. And remember that OS X can’t format a drive in NTFS.
If reformatting the drive isn’t an option, your Windows friends will have to install software that allows Windows to read Mac-formatted drives. One of the best utilities for this purpose is MediaFour’s MacDrive ($50).
Different drives, different formats
|Format||Used Primarily By||Windows||OS X||Best Use|
|FAT32 (File Allocation Table [32-bit])||Windows||Y||Y||Y||Y||Swapping drives back and forth between Macs and PCs.|
|NTFS (New Technology File System)||Windows||Y||Y||Y||N||Reading a Windows-formatted drive once and not needing to send it back with Mac data.|
|HFS, HFS + (Hierarchical File System)||OS X||N||N||Y||Y||Sharing drives with other Mac systems and with Windows systems that have MacDrive installed.|
|UFS (Unix File System)||Unix||N||N||Y||Y||Sharing hard drives with certain Unix systems, but not with Windows.|