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I recently bought a Sandisk Cruzer USB drive. Part of the drive (6.66 MB) is formatted with CDFS and shows as a CD drive.

Why do they do this ? Is it to protect the software on that part of the disk to trick the OS (Vista) into not overwriting or amending, because it thinks this is a read-only CD ?

Is the 6.66 MB significant. Apart from being associated with the Devil ?

How can I format a partition on a USB drive to be CDFS ?

Why would I want to do something like that myself on my other flash drives ?

I'm a programmer, so how can I leverage this new knowledge ? Any Ideas ?

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CDFS isn't an actual filesystem (to my knowledge); usually CDs use ISO9660 or UDF as filesystems, and Windows systems display "CDFS" when showing individual tracks on audio CDs. – quack quixote Apr 11 '10 at 23:15

This is part of the U3 software that comes on it. It is garbage and I always remove it, the link for the removal tool is here:

Keep in mind, this will format your drive.

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Most likely the reason they did this was to prevent overwriting their software from the flash drive.

If desired, you should be able to change the partition scheme to fully utilize the drive. The easiest way to do this is to boot into a Linux LiveCD and use gParted to fix it. Offhand I can't remember any free partition managers for windows.

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EASUS partition master home edition is a pretty good free partition manager for Windows. You can find the software at this url – ephilip Sep 1 '09 at 18:55

Does the pseudo-CD have an autorun.inf file on it?

This is sometimes done to take advantage of the CD autorun feature. When one of these devices is plugged into a computer that has autorun enabled, a program on the drive will start automatically. This is typically a small pop-up menu that allows the user to run, install, or uninstall programs from the drive.

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indeed it does. I'm hoping to utilise similar functionality for myself actually. – cometbill Sep 6 '09 at 13:08

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