Cannot format USB stick under OSX

Discussion in 'Mac OS X Lion (10.7)' started by nuwonda, Aug 29, 2011.

  1. nuwonda macrumors newbie


    May 30, 2008

    I searched the internet high and far and have found many formatting issue posts all around but none that covers this particular error.

    I have a USB Stick with the following specs according to Disk Utility:
    Name : Udisk Udisk 2.0 Media
    Type : Disk

    Partition Map Scheme : Unformatted
    Disk Identifier : disk1
    Media Name : Udisk Udisk 2.0 Media
    Media Type : Generic
    Connection Bus : USB
    USB Serial Number : 0001CFCFCFC5DB1C
    Device Tree : IODeviceTree:/PCI0/EHC1@1D,7
    Writable : Yes
    Ejectable : Yes
    Location : External
    Total Capacity : 2.07 GB (2,066,743,296 Bytes)
    Disk Number : 1
    Partition Number : 0
    S.M.A.R.T. Status : Not Supported

    I can format the stick just fine in Windows but every time I try to erase the Stick or use the partition menu in Disk Utility it starts trying to "Unmount" the device until it times out with the following error:

    2011-08-29 19:39:26 +0200: Preparing to erase : “Untitled”
    2011-08-29 19:39:26 +0200: Partition Scheme: GUID Partition Table
    2011-08-29 19:39:26 +0200: 1 volume will be created
    2011-08-29 19:39:26 +0200: Name : “Untitled”
    2011-08-29 19:39:26 +0200: Size : 2.07 GB
    2011-08-29 19:39:26 +0200: File system : Mac OS Extended (Journaled)
    2011-08-29 19:39:26 +0200: Unmounting disk
    2011-08-29 19:42:01 +0200: Disk Erase failed with the error:

    Wiping volume data to prevent future accidental probing failed.
    2011-08-29 19:42:01 +0200: Erase complete.
    2011-08-29 19:42:01 +0200:

    After that the stick becomes unreadable and when plugged in again you get prompted that the stick cannot be read and OSX gives you the option to "Initialize..." which ends in Disk Utility again getting stuck on the "Unmounting" of the device.

    I even tried from the terminal with "diskutil partitiondisk disk1 JHFS+ newdisk 100%" without success, aside from the fact that I was able to get this error number:
    "Error: -69825: Wiping volume data to prevent future accidental probing failed"

    On top of the USB Stick listing in Disk Utility, it also lists a greyed out CDROM Icon Entry for the stick "Udisk Udisk 2.0 Media", can't do anything with that.

    I tried formatting this stick in all ways I can think of on a MAC under OSX and it just does not work.


    Thanks for any input!

  2. bitsltd macrumors newbie

    Oct 25, 2011
    It's a Lion problem

    I had to fix it on my Snow Leopard system.:mad: If you find a Lion fix, please post it.
  3. xgman macrumors 601


    Aug 6, 2007
    Can you "remove all formatting" in windows and then try again as new in Lion?
  4. inteljoe macrumors newbie

    Jan 19, 2009
    Boston, MA
    Yeah, the UDisk is a SanDisk drive partition for there software suite that comes with there USB drives.

    You have to use a Windows (XP or greater) computer and run the UDisk software. If you go to the settings or tools portion there is a removal tool that will let you remove that partition.

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