Reformatting external disk


macrumors 68040
Original poster
Feb 7, 2011
Hi all, I'm asking this on behalf of a freind who has a macbook running os9. She got an external disk drive that she initally formatted in windows to copy files that were on a win 7 machine. Now she wants to reformat this disk to work with her macbook - and I don't really have a clue about mac.* How to proceed? Is there any way to safeguard the data already on the disk?

*Came to macrumours because of my iphone and stayed cause it's interesting and a change from my usual forums.
Nov 28, 2010
Show her this guide, but know, that formatting a drive will delete its data, thus any data, that is on that HDD and needs to be saved, has to be copied to another HDD, be it another external HDD or the internal HDD of the Mac.


macrumors 6502a
Mar 19, 2012
ExFat partitions can be used with both Windows 7 and her Mac.
ExFat is decidedly less redundant than FAT32. FAT32 has a second copy of the FAT, but ExFAT does not so if that one and only table is corrupt - well that is that. ExFAT is also not journaled, which while that doesn't make a file system more reliable, it often does make repairs faster on large disks with lots of files.

I would leave it formatted NTFS, and enable read-write mounting by editing /etc/fstab (use vifs). Or consider a 3rd party NTFS solution.