flash drive reporting wrong size, how to fix?

[Patrick O'Callaghan]

On Sat, 2012-01-14 at 22:52 +0000, Ian Malone wrote:
> Hi,
> 
> I've got a 2GB microSD card that I've been using a while (so I'm
> confident that at one point it was a 2GB card and isn't a 'fake').
> Recently it stopped responding (the last place it was used was in my
> phone) and on plugging it into my computer (I've got two separate
> adaptors, one a USB-microSD, the other a microSD-SD and have tried it
> in two machines) it now shows up as having no partitions and an
> unpartitioned capacity of ~48MB. I suspect it's failed somehow and
> they're not expensive to replace, but I'd be interested to know if
> there are any tools that I could use to try and re-program it to show
> the correct size again. Any suggestions?

Use fdisk to check the partition table. The drive should have at least
one partition.

Use mkfs to make a filesystem.

If you want device portability, you should probably create a VFAT
partition and use the VFAT option to mkfs.

However I have had cases where this doesn't work well, especially with a
USB flash drive -- not a microSD -- that's been used a lot. I've had to
format the drive on a Windows machine, which (so far) has always
recovered it.

poc