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crouchie 01-12-2011 12:58 PM

Weird problem transfer files from SD Card to USB Memory key
Hi all, hoping you can help me on this one or set me straight if I'm missing something.

I recently picked up a Mac Air to use as primary work machine. It has only limited solid state storage so I have opted for a 128GB USB memory key as the location for music and photo files leaving me with enough space on the SSD for everything else. I previously had music on an SD card that was permanently in the card reader of my old Vaio and now I want to transfer these files to the USB memory drive. I'm using a memory card reader plugged into one USB port and the USB (Kingston - FAT32 format) drive plugged into the other USB port. OS is 10.6.6

The weird thing thats happening is not all the files are copying when I select copy and paste them from one storage media to the other. The result is missing sub-directories when the job is reported as completed and an amount of data that is less than the original card's contents. I can copy Music directory to the USB memory Key, but when I examine the result the new 'Music' folder has less data and not all sub-directories. I've tried moving it all (17Gb of data) in one lump as well as chunk by chunk. I;m not a novice to mac, but not an expert either - on Windows this job would be pretty simple - can't work out what;s going on here though. Could it be the USB memory key? I did erase and re-format it in Disk Utility.

Any ideas appreciated.


chscag 01-12-2011 02:47 PM


Could it be the USB memory key? I did erase and re-format it in Disk Utility.
No, it's not the key. It's probably the way you formatted it. When using Disk Utility to format a drive or storage device to FAT-32, DU defaults to using the GUID partition scheme. That creates a small 200MB EFI partition on the storage device and can interfere with storage capacity and file transfer.

When formatting a device to FAT-32 using DU, you must select options at the bottom of the dialog and switch the partition scheme to MBR. Then the device will be formatted and partitioned correctly.

crouchie 01-12-2011 07:50 PM

Thanks CHSCAG - I'll give that a try. Appreciate you help.

crouchie 01-12-2011 08:25 PM

drifted Ratesion
Just checked the existing format and I think it is already setup as MBR. Here are the details showing when I look at the drive in DU;

Disk Description : Generic Flash Disk Media Total Capacity : 135.08 GB (135,083,851,776 Bytes)
Connection Bus : USB Write Status : Read/Write
Connection Type : External S.M.A.R.T. Status : Not Supported
USB Serial Number : 712088F1 Partition Map Scheme : Master Boot Record

Back to square one...

Any other ideas of what might be causing this?

Another alternative is to do the file copy/paste using windows 7 running on parallels, but this just seems/feels like giving in - I'd prefer to sort it out in OSX if I can.

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