[Update July 2017: SanDisk’s Cruzer USB flash drives have not included U3 partitions for a few years so this information is not very relevant any longer.]
For years, SanDisk’s Cruzer USB flash drives have been partitioned into two parts. One part is named U3 and contains some Windows-only software that can be used to protect files stored on the other partition. This software is useless to Mac users and the U3 partition just becomes an annoyance. So, many people have wondered how they can delete this U3 partition. Until recently one needed to download and use a Windows-only application made by Cruzer. Finally, in Jan 2010, Cruzer released a Mac application which can be used to get rid of the U3 partition.
You can download the application here.
Once it’s downloaded you can open it and start its installation. Be aware that installation will require you to restart your Mac.
After the restart you’ll find several applications in a folder named “SanDisk Cruzer” in your /Applications/Utilities folder.
Open up the application named “LaunchPad Removal Utility for Mac” and follow the on-screen instructions. I found one part of the instructions confusing. It asks if you want to backup the data. I thought it was referring to the data on the other partition, but that is apparently not the case. I figured out that it was only referring to the data on the U3 partition, not the data on the main partition where you put your files. So, I told the application to go ahead and remove the partition without backing up data. I waited 30 seconds and it finished the process successfully and all of my data on the main partition was still intact.
Even though I told you that the application won’t erase your data on the USB flash drive I still recommend that you backup the data on the USB flash drive just in case something goes wrong. I don’t want you to lose any of your data.