USB: PC can't read MAC FAT32 MBR partition

Question

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USB: PC can't read MAC FAT32 MBR partition

Hello,

I really hope someone can help me out on this one. Thanks in advance for trying. 😊

[Background info]

I partitioned my 16GB USB stick in 2 partitions. One partition has a Mac OS Extended (journaled) structure. I use this partition for Time Machine. The other partition has an MS-DOS (FAT) structure. The partition table is MBR, so I thought my PC should be able to read and write on that partition.

[Problem]

However, when I put the stick into my PC it wants to format it again. At first I thought "Ok, I'll just format it". Then it turned out te Mac partition got formatted, which I used for Time Machine. So I had to create new partitions and a new backup all over again. 😠

[Solution]

So, what to do? Does any of you have a clue how I can let my PC read and write on the partition? Please help.

Sincerely,

Bernd

MacBook Air, Mac OS X (10.6)

Posted on Aug 24, 2011 2:26 PM

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Answer 1

Fortuny

Level 7

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Aug 25, 2011 5:21 AM in response to ebarnd

Maybe it helps if you revert the order of the partitions, making the FAT32 partition the first one and the MacOS the second.

I admit though that I never tried anything like this on my USB-Sticks.

Stefan

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Answer 2

Aug 25, 2011 5:42 AM in response to ebarnd

In any case, that's nowhere near enough space for TM. You need at least the same capacity as the internal HD (or SSD) and preferably about 1.5 X.

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Answer 3

ebarnd Author

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Aug 25, 2011 3:15 PM in response to Fortuny

@Fortuny: I could try to revert the partitions. I've thought of that too, but I think Time Machine won't backup if I do that. Still, it might be worth a try.

@noondaywitch: Time Machine asked for at least 7,88 GB of space. So I partioned 7,9 GB and it backed up succesfully.

Anyway, when I run compmgmt.msc (Windows) and go to 'Disk Management' it says the File System of the partition I want to use for data is RAW. 😕 Do you think this might have something to do with the issue?

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Answer 4

Aug 25, 2011 3:25 PM in response to ebarnd

"Time Machine asked for at least 7,88 GB of space. So I partioned 7,9 GB and it backed up succesfully."

But it won't be able to do incremental backups. Time Machine is not for one-off backups, it's purpose is to back up regularly, adding new data but preserving the original backup so that you can, eventually, retrieve files or a system from several months ago, even after stuff has been deleted in subsequent times.

Note also that a TM backup isn't bootable.

Here's some reading on TM; http://web.me.com/pondini/Time_Machine/Home.html

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Answer 5

ebarnd Author

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Aug 25, 2011 3:43 PM in response to noondaywitch

Oh .. I see. Thanks for the link.

I suppose you're right. Anyway, in that case I could do the same with my external HDD. I would create a partition for TM backups and the rest of the space would be used for a Windows parition. Then basically my question didn't change, right?

Or perhaps I should just buy one HDD for MAC and one for Windows and stop asking difficult questions. Hmm.. I just can't stand I can't get this thing working. 😝

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Answer 6

Aug 26, 2011 4:15 AM in response to ebarnd

Personally, I would always keep TM on a seperate hard drive all to itself; it saves a lot of complications and potential pitfalls.

No reason why you can't use a FAT32 or exFAT (aka FAT64) drive to transfer files from PC to Mac and vice versa. Usually that works after formatting on the Mac, but it sounds like your PC doesn't like it, so back up the data on there and reformat on the PC. Check the Mac can read it ok before using for serious work.

Note that exFAT is only supported by the latest OSs on both Mac and PC so it'll depend what you're running on each (both need to be compatible)

FAT32 isn't too bad, but it does a have a file size limit of around 4GB.

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Answer 7

ebarnd Author

Level 1

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Aug 26, 2011 7:42 AM in response to noondaywitch

Alright, I'll do that.

Anyhow, formatting on a Mac isn't the problem. I did that before and my PC had no problems reading the data.. so.. I'll just use two hard drives, hopefully without any problems. Thanks for your help.

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