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i popped a 1gb usb storage device into a desktop install of ubuntu 10.10 and tried to delete a few files but noticed it is read only.
the permissions say that user 99 was the creator and when i open gparted, it shows dev/sdc1 all the way through dev/sdc8 as unknown filesystems of sizes between 31.5 kib and 256 kib. the filesystem that has stuff on it is hfs+ on dev/sdc9. i would like to get the files off and understand what could have caused this.

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up vote 1 down vote accepted

I would suggest overwriting the USB stick with zeros and then repartition it (as root):

dd if=/dev/zero of=/dev/sdc

(/dev/sdc might change, so doublecheck if that's your USB drive!)

After it finished writing, do a sync, and you should be all set.

And then repartition it with gparted, or whatever your favorite partitioning program is. You need to create a new partition table. Then, you can add new partitions.

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Oh, I forgot to answer what might have caused this: Ever pulled out a USB drive without syncing/unmounting it? It might be something totally different, though. – polemon Mar 19 '11 at 1:42

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