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I bought a 16G SD card to put Android on to put in my Nook Color. I downloaded a Honeycomb distribution and wrote the disk image to it. Then I found the Nook Color takes Micro-SD cards, and decided to use this SD card for casual file storage and sneakernet.

Right now, it reports its size as 117 MB. Sticking it into a Windows 7 computer, I can reformat it in several different ways, including NTFS and FAT variations, but always 117 MB. The reformat to default configuration shows 117 MB.

Is there something I can do to make this hold actual GB again? Any ideas what happened?

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Use disk manager. It sounds like there are two partitions and one is unalloacted. – Ramhound Oct 28 '11 at 13:13
@Ramhound: Actually, there's four partitions, and Disk Management shows the little one as the active one. So far, I've been unable to delete that partition (there's another one I haven't been able to delete). and can't seem to move the active partition, or create another partition out of 12 gigs of unused. The help provided is useless for this purpose. – David Thornley Oct 28 '11 at 23:09

When you copy a raw disk image to the card, you copy the partition table with it. In many images, there is one small partition (to fit into all media) and the remaining space is simply unallocated – you can create a second partition there, or extend the first one.

Unfortunately, Windows does not support multiple partitions on removable drives and disables the usual management functions. There's still a way to fix your card:

  • Boot into a Linux live CD (Ubuntu is okay), then use GParted or command-line parted to resize or create partitions.

  • Alternatively, if you don't mind losing all data, you could use dd or a similar tool to completely zero out the partition table (first 512 bytes); after this, Windows will ask to "format the disk" creating a new partition in the process.

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There's a third method: use diskpart's clean command – Bob Mar 8 '14 at 13:48

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