Problems with Formatting Flash Drive for Mac and PC

Discussion in 'Mac Basics and Help' started by mistnycegai, Jun 23, 2010.

  1. mistnycegai macrumors newbie

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    Jun 23, 2010
    #1
    I've been searching for awhile but I haven't been able to find anyone with any solutions or anyone with my exact problem. Sorry if I missed anything and am reposting an existing issue.

    So my exact problem is that I usually use my Flash between my Mac and other PCs. And I just installed OSX Snow Leopard from my 8GB Kingston Flash. Now I know to use Disk Utility to reformat to MS-DOS (FAT) to be able to to use it between the to OSs again.

    So I do that but PCs won't read it and ask me to reformat it again. I'd happily do that cuz I know as long as it's in FAT or FAT32 the two OSs will be able to read and write from each other. But the PC only recognizes 200 mb and when I do reformat it on the PC there are now 2 different Partitions. One being the PC's 200 mb in FAT and the other Mac's almost 8GB MS-DOS.

    I've tried a few different things too. I've tried Partitioning the whole thing over again int MS-DOS after having erased everything. Which I see only causes the Flash drive to shrink from 8.01 GB to 7.80GB and still isn't readable by a PC.
    Then I tried Erasing it to free space but PCs still don't recognize it and still ask me to reformat the 200mb is sees on the Flash.

    Please if anyone can help it would be Greatly Appreciated! Thanks much to anyone who can help me.
     
  2. Hellhammer Moderator

    Hellhammer

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    #2
    Download NTFS-3G for your Mac and format it to NTFS with Disk Utility. Now both OSs can read&write it fine plus it support +4GB files
     
  3. mistnycegai thread starter macrumors newbie

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    Jun 23, 2010
    #3
    Hey thanks but it didn't help. Maybe there's something physically wrong with my Flash drive though I have exactly no idea what. I've tried different things multiple times.
    I format then try it on the PC. It still only sees 200MB. Then I tried formatting it again then partitioning it with Free Space. Then I partition the whole thing using that new NTSF format.
     
  4. Hellhammer Moderator

    Hellhammer

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    #4
    Erase the whole drive and use NTFS format, that should do the trick. Also, try formatting it on the PC (Disk Management or whatever was the app)
     
  5. Eidorian macrumors Penryn

    Eidorian

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    Indianapolis
    #5
    I've had this happen before. Your flash drive is probably using a GUID Partition Table. You can change the partition type to Master Boot Record using Disk Utility.

    What version of Windows are you using?
     
  6. mistnycegai thread starter macrumors newbie

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    Jun 23, 2010
    #6
    So How exactly should I erase it all?
    These are the steps I took.
    1. format it to MS-DOS (FAT)

    2. Put a file in the drive to test on PC. PC wants me to reformat the only 200MB of free space it can see.

    3. Then I tried partitioning. (partition tab) 1 Partition formatted to Free Space

    4. Reformat the free space to NTFS-3g.

    5. Try testing it on PC again. But it still only sees an unformatted 200MB

    So I can't format it on the PC except for that 200MB is recognizes.The Flash drive worked with PC and MAC before I used it to install Snow Leopard.

    So How do I do this Master Boot Record thing. And I've been testing it on a PC with vista. Might that vista thing be a problem in it's self? hehe
     
  7. Hellhammer Moderator

    Hellhammer

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    #7
    I'm not on my Mac atm so I can't check it but I think it's in the partition tab where you can select the partition table

    To erase it, go to erase tab (select the disk, not the partition) and then just select NTFS as format and click erase.
     
  8. mistnycegai thread starter macrumors newbie

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    Jun 23, 2010
    #8
    THANK YOU THANK YOU THANK YOU!!! I figured it all out =) it was in fact in the GUID Partition Table and got it to Master Boot Record through the option button in the partitions tab. It works perfectly with both now using that NTSF-3G.
     
  9. Eidorian macrumors Penryn

    Eidorian

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    Indianapolis
    #9
    Yeah, it's in the Partition tab and not just under Erase.

    I had a flash drive that wouldn't mount on my XP machines but it would work just fine under Windows 7.
     
  10. Mystikal macrumors 68020

    Mystikal

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    Irvine, CA
    #10
    I know this is an old thread but can someone go into more detail. This problem is fixed on my 3gb drive but my 8gb drive is still showing 200mb. How do i change the boot to master boot?
     
  11. Hellhammer Moderator

    Hellhammer

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    #11
    I just tested this.

    1. Erase it first and use FAT format.
    2. Go to partition tab and you should see one partition. Click it and click "-", that will delete the partition and you should now have a blank disk. Then, click the "+" and it will add a new partition which is the size of the drive. Now, the options should be available to click. Click it and select Master Boot Record.
    3. Click execute and you're done
     
  12. hardrock121 macrumors newbie

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    Jul 22, 2009
    #12
    why dont i see the partition tab?

    I am in the disk utility and i don t see the partition tab..what i m doing wrong??
     
  13. Hellhammer Moderator

    Hellhammer

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    #13
    Try erasing it and choosing a different format. IIRC Master Boot Record can't be partitioned
     
  14. andalusia macrumors 68030

    andalusia

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    Manchester, UK
    #14
    I think you're correct about MBR not being able to be partitioned (at least not without formatting the drive first). I had this issue a few weeks back, very irritating.
     
  15. andrey323, Nov 1, 2012
    Last edited: Nov 1, 2012

    andrey323 macrumors newbie

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    #15

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