Bizarre USB Flach drive problem. Formatted on MAC, no-go in PC. Won't reformat @ 16GB

Matt_Stevens

Senior member
Dec 17, 2009
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OK, this is strange. My friend sent me two 16GB Sandisk USB Flash drives that he (claims) formatted as NTFS on his MAC. He tested them on his friend's laptop that runs Windows 7 and they worked fine.

Not here though. When I insert the drives it wants to reformat. There seems no way around this. And worse, it wants to reformat at 200GB!

WTF?!

I've researched as much as I can and am stumped.
 
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kmmatney

Diamond Member
Jun 19, 2000
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I think the nest thing you can do is to try them on a few other machines, and maybe on a MAC as a last resort. If that doesn't work, you may be out of luck.
 

fzabkar

Member
Jun 14, 2013
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Use a disc editor to upload the contents of sector 0. That will show us what is going on.

DMDE is a good freeware editor.
 

Matt_Stevens

Senior member
Dec 17, 2009
460
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81
I am going to check into DMDE now. I would have replied earlier but I threw my back out. Not fun.

Unfortunately I really do not have access to any other machines. The one person I know with a MAC is on vacation until August. I did try it on my landlord's PC and had the same result.

EDIT... Here is what DMDE sees:

dmde_driveinfo.jpg~original
 
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fzabkar

Member
Jun 14, 2013
141
32
101
The problem appears to be that your drive has a superfluous EEh protective MBR partition in addition to the actual 07h NTFS data partition.

I think the easiest solution would be to write zeros to the EEh partition table entry. If you could display sector 0 in hex mode (Mode -> Hexadecimal), then I could show you what to edit. BTW, this change is easily reversible.