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I've just bought a 500GB usb hdd and I saw it has one primary FAT32 partition using all the space... sounds good...
Then I tried some configuration and finally needed to reformat hdd with a single FAT32 primary partition but... surprise, now Windows XP permits this nor some live linux distro: they make me create this kind of partition using maximum 384GB.
Why? Am I stupid? Am I doing a silly mistake or what?

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some forums recommend gparted on a livecd (bootable linux usb/cd), apparently Windows 7 will also format 500GB FAT32. – PP. Apr 28 '11 at 22:53
@PP: I've already tried with GParted live, but the result was the same. I will try with Seven and let you know. Thanks – Marco Apr 28 '11 at 22:59
up vote 1 down vote accepted

See Microsoft Support Article about FAT32 Limitations with Windows XP. It says that the maximum disk size is approximately 8TB.

The maximum number of clusters is 268 million. The maximum cluster size is 32KB. So you've got to work out how to format using a larger cluster size.

Update: try the FORMAT command with the following flags:


The /FS sets the filesystem type and the /A sets the default allocation unit size.

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curious: I tried using format as you said, but up to 64k it say it's too low, but from 128k it's too high!! So, the only solution is to use exFAT in Seven? Sounds strange... What do you think? – Marco Apr 29 '11 at 11:40
I've accepted your answer not because it was correct, but for your perfect comment on exFAT on Seven. Thanks a lot, you solved my problem anyway :) – Marco Apr 30 '11 at 16:41
@Marco I'm sorry you were not able to solve the problem, I was hoping (though I could not try) a variation of the format command would do what you wanted. – PP. May 8 '11 at 0:50

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