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I just purchased a new 16GB Sandisk Cruzer USB drive, it has drive that it mounts called U3. It is windows only and I downloaded the Cruzer utilities for mac to remove them.

The thing is I have no idea what it is or what it is used for. Does anyone use U3 and find it beneficial ?

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up vote 7 down vote accepted

From the Wikipedia article on U3:

U3 is a company producing a proprietary method of auto-launching applications from specially formatted USB flash drives. Flash drives adhering to the U3 specification are termed "U3 smart drives". U3 smart drives come preinstalled with the U3 Launchpad, which looks similar to the Windows OS start menu and controls program installation. The method works with recent Microsoft Windows systems only. Applications which comply with U3 specifications are allowed to write files or registry information to the host computer, but they must remove this information when the flash drive is ejected. Customizations and settings are instead stored with the application on the flash drive.

I don't personally use the U3 software, but some less technologically-inclined people in my office appreciate having the file management built into their flash drive. You can also install portable applications onto the drive, but again, I find it easier to maintain my flash drives myself and use

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Oh I get it ... This is because Microsoft changed the behaviour of Windows 7 for flash drives to close a security hole. – Bruce McLeod Aug 1 '09 at 7:11
Bruce: Windows has never started anything automatically from flash drives - so U3 drives from the beginning presented itself as both the actual drive and a virtual CD-ROM that contains the launcher. (Windows has no way to know if it's actually a CD-ROM or not.) – grawity Aug 1 '09 at 7:17
I've even got the u3 installer once to install a portableapps booter, instead of u3 crap. – Dykam Aug 1 '09 at 13:35
Dykam: My friend likes replacing U3 with a keylogger, and leaving in certain places at school. – grawity Aug 1 '09 at 17:02
auto-starting applications from USBs is the best way to spread viruses – hasen Aug 17 '09 at 20:05

I use U3 on a USB drive that I use for work to secure my employer's data. It works fine in this total Windows environment however, I've always wondered how adequate the security is.

I remove it from my personal USB drives I use for home and travelling, because I don't always use a computer running Windows.

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Can I ask how you removed it as I recently purchased a USB stick with U3 on it and I want it gone. – smack0007 Sep 3 '09 at 18:20
Gee, that would be a good question to post! Answer is at – Michelle Sep 4 '09 at 21:31
Thanks so much. – smack0007 Sep 8 '09 at 18:36

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