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partition size not a multiple of 4k

when formatting an external HD today [Mac OS Extended Journaled(HFS+)] i ran into the following error.

"partition size not a multiple of 4k"

after a quick google search, i found the following fix:

"When formatting using Disk Utility, remember to select GUID Partition Table as your "partition map scheme" instead of MBR (Master Boot Record)."

basically do as follows:

    1. open disk utility
    2. select the drive
    3. select the "partition" section
    4. under the volume scheme select the number of partitions required
    5. select the "options" button
    6. make sure "GUID Partition Table" is selected NOT "Master Boot Record"
    7. click apply

you now should be good to go and the drive should function correctly. yay!

  • Thank you for this instruction.
  • you are very welcome =)
  • Frank Compernolle
    Thank you so much, this helped me a lot!
  • glad to help =)
  • Eric Greenwald
    Thank you!!!!!!!!!
  • azul
    I'm having the same problema when trying to follow this in Tiger, to format a Lacie disk.

    I can't find the “partition” section in Disk Utility. What am I doing wrong?...
  • hmm... i don't have a machine set with tiger here, I will update this when I am at work with info from one of those machines.
  • Joe
    Ah! exactly what I needed, thank you.
  • thsi saved my day. thanks.
  • glad it helped!
  • James
    Thank you so much for posting that. It got my 1TB Western Digital Drive to work perfectly, and all because the partition was wrong! Tried formatting so many times and about three Drive Management programs. Nothing worked then read this! Good work my man!
  • i am very happy it helped you, this issue caused me much grief as well =)
  • THANK U SO MUCH!!!! 10000000000000... Kisses!
  • Bless you!
    and curse Apple!
  • JENN
    Thanks so much!
  • your very welcome!
  • Sam
    Awesome!
  • Nico
    Thanx lot! Great!
  • wow cant believe this post has helped so many people. glad to know i made a small difference in your day =)
  • dude, thanks. :D
  • jsnowboarder67
    Nice... saved me a return or 2
  • Rohail Hyatt
    God bless you for posting this info! It helped :)
  • homer
    THANKE YOU DUDE! YOU ARE THE BEST!!! :o)
  • Eyemac99
    You saved the day, dude. Thanks so much for the tip. SHAME ON SimpleTech for not including that info in their directions !!
  • Frode
    Thanx man.

    Somebody should tip Apple about this pitfall. Obviously this is something that a lot of people have trouble with, so it should be made easier.
  • In addition to the steps listed above, I found it necessary to first erase the Fat32 volume. That's the lower indented volume name in the Apple Disk Utility window (on the left side). It's counter-intuitive, but if you think data loss, it makes sence. After erasing that volume with Fat32 selected, I could then repartition the drive, selecting HFSplus and GUID in the Options. Before this, it kept putting up errors when I tried to repartition.
  • Nadia712
    Holy good god, thank you so, so, SO much for this. I would have never figured this out on my own, and I'd been trying to "fix" my new hard drive for days without success. THANK YOU.
  • Im very glad this was able to help you. I remember how I racked my brain over this. It was rather frustrating, so I totally understand.
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