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I got a free promotional USB stick that I want to format for my own purposes. When I inserted it, it automatically opened a browser and launched a web site.

I have since disabled autoplay on this computer so that nothing launches when the stick is inserted. But it still shows up as two separate drives, and one of them is a "CD Drive" that I can't format.

How can a USB stick contain a "CD Drive?" And more to the point, how can I remove this partition using Windows XP or Ubuntu?


I previously asked for an XP solution, but finding none, I have tried Ubuntu, also without success. Gparted doesn't see the "CD" portion as a device at all, and from bash, any chmod changes I try tell me that the file system is read-only. Any ideas?

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+1 because I had the exact same question last year.… – mmyers Jan 7 '10 at 16:04
possible duplicate of How can I make a USB flash drive appear/not appear as a CD drive? – Synetech Mar 13 '12 at 5:14
up vote 5 down vote accepted

Sounds like this is a customized U3 drive!

U3 is a technology that, along with functioning as a normal USB data drive, also can emulate a CD-ROM station.

The virtual CD-ROM partition can not be modified normally, and is not "burnable" in the traditional sense. However, it can be modified and even disabled with specific tools.

To remove the virtual CD-ROM drive, you would need an U3 uninstaller available at [broken link, redirects to a different domain]

You should also be able to remove it under Ubuntu, with the help of (I would recommend trying the latest version, the one that came from the Ubuntu repositories did not work on my U3 USB stick)

A note of warning though: The u3-tool above is not guaranteed to work on your specific drive, and may (though it has not happened to any of my drives before) mess it up. Use at your own risk. I would recommend using this as a back-up if the official U3 uninstaller does not work.

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I still haven't got around to actually doing this, but your answer seems to be the most complete one here, so you deserve an acceptance. :) – Nathan Long Dec 21 '10 at 18:38
the u3 uninstaller link is broken. – matt wilkie Apr 9 '11 at 4:17

I had the same issue, but my USB drive seemed to be a branded Transcend Jet flash model for which I used this tool: CD-ROM_Remover_v1.0.0.3.rar (source)

For those who don't know the exact model of the drive you need to get the VID and PID of the USB drive and search it in a online database (similar to

PS: Make sure you also check the duplicate questions for additional ideas.

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Use the HP program for flash disks located at:

If you can't find it there, google for "hp usb disk storage format tool". It is the HP format utility for flash disks, but works on any brand of flash stick. It automatically, as part of the format process, removes partitions.

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My problem USB stick was from U3. It showed as 2 drives as noted above -- a large FAT32 and a small write-protected CDFS partition. Normal Windows management or DOS format did nothing for the CDFS partition. Kept telling me the CDFS partition was write protected.

The solution was to open the Launchpad.ZIP file that was on the small partition, select the UninstallLaunchpad.exe file in the zip, and run it (can do that from within ZIP, no need to un-zip to anywhere). This utility warns you gently about it removing data, but what it is saying is that the ENTIRE USB STICK will be erased. Works like a charm though.
After program completion I now have a single writ-eable FAT32 partition USB stick. It simply formatted the entire stick into a single partition (drive).

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use the HP USB Disk Storage Format Tool to format the USB drive and remove all partitions.

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Remove it with the Windows (2000 and higher) Disk Management tool.

You can't have a CD drive on the USB stick. It just shows up that way so you can't add or remove any info on that partition. Basically having it labeled as a CD drive makes it read-only.

You can also boot up a Linux live CD, or other boot disk with gparted. Use gparted to remove the extra partition and merge it into the other one. Keep in mind not all boot disks will let you see USB drives, though, to edit the partitions.

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