Problem with win32diskimager

Hello all;

I got unexpected results when I used Win32DiskImager to create an image of a uSD card I had just prepared.

It seems that no two 8GB uSD cards have EXACTLY the same number of bytes, do if you make a back up image of a

uSD card that is just slightly bigger than another 8GB card (even from the same manufacturer) then you can’t copy it to the smaller card.

To get around this problem, I used fdisk to create an installation that was about 6GB in size.

When fdisk asked for the last sector I gave it a size of “+6000GB” instead of accepting the default.

I thought that by doing this I would end up with a ~6GB image from Win32DiskImager.

Instead, I got an 8GB image. (The approximate size of the uSD card I used.)

Am I doing something wrong here, or should I try and using Linux “DD” instead ??

I have never used “DD” before.

Thanks again;


“No one could make a greater mistake than he who did nothing because he could do only a little.”

“All that is necessary for the triumph of evil is that good men do nothing” Edmond Burke (1729 - 1797)

I don't know if this is the same problem.

I have created disk images to burn on to previously used SD cards of the same size only to find it runs out of space near the end.

Using dd fails to reclaim all the space.

Under Windows, formatting the card using SDFormatter clears it up and the image fits.

Heya William,

Thats kind of odd, although not totally unexpected I think. Anyway I was thinking, that you could write a script in Linux to do all this for you. Then if I understand you correctly, this script would / could create the partitions, format them correctly, then copy all the boot file to the right locations, and lastly untar a tar’d archive for the rootfs onto the second partition.

BTW, I’m not coming down on Windows here, I just think Windows is the wrong tool to use for this job. I use Windows on my own desktops as well . . .