|Formatting for MAC OS9+ and Win98SE = FAT or FAT16.|
(The link does not go to the FAQ. You have to navigate to it and then use the Search = format to find this following lengthy answer:
Customer needs to transfer images, music, documents, or other data files between a PC with Windows 98SE or later and a Macintosh system with Mac OS 9 or later installed. And vice versa.
• A Macintosh computer with Mac OS 9, version 9.2 or later installed
• A PC computer with Windows 98SE or later installed
• A SanDisk Cruzer family product which is compatible with both systems
• If you are unsure about system compatibility, please go to www.sandisk.com for more product information
Notes and Warnings:
• Not all Cruzer products are supported with Windows 98SE or later, or Mac OS 9 or later. Please check with SanDisk technical support if you have any questions regarding supported operating systems.
• Though SanDisk Cruzer products with U3™ Technology will work as a standard USB drive on the Macintosh systems, the U3™ applications will not work. Be sure to drag the U3 SYSTEM icon as well as the drive icon to the trash before removing your U3™ Technology device.
• Initializing or Formatting your Cruzer or SanDisk flash memory card will erase all files on the card. The files may not be recoverable. Please backup your files before initializing or formatting.
• Do not partition your Cruzer or SanDisk flash memory card. Repartitioning may make the flash memory device unusable on other computer systems.
1) To copy or move files between a Macintosh and Windows PC, use the FAT file system
2) SanDisk Cruzer products are shipped ready to use on both Windows PC and Macintosh systems. In most cases, you will not need to reformat or reinitialize your SanDisk Cruzer to transfer files between a Windows PC and a Macintosh system. If you need to reformat or reinitialize a SanDisk Cruzer, please ensure the following:
• On a Windows system, format your Cruzer with the FAT or FAT16 file system.
• On a Macintosh system, format your Cruzer with the MS DOS file system.
• Once the Cruzer reformatted or reinitialized as FAT/MS DOS, it can be used to move images, music, documents and other data files between the Macintosh and Windows PC systems.
*If you need help formatting your Cruzer, please see FAQs on Cruzer formatting for your operating system, or consult the documentation for your computer for more information.
3) Once all files you need to move between systems are copied to the SanDisk Cruzer be sure to follow the steps for your computer to safely remove the device before detaching and moving your Cruzer to the other computer system. Once it is safe, detach the Cruzer from the USB port.
• On a Windows system, click on the Safely Remove Hardware icon in the task tray, and then choose the drive associated with your Cruzer. Once the Cruzer has been stopped, Windows will inform you that it is safe to remove the device.
• On a Macintosh system, drag your Cruzer to the Trash before removing it from the USB port. Once the drive icon has been removed from the Macintosh desktop, it is safe to remove the Cruzer.
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I don't know what the U3 system is that they refer to in their FAQ but it speaks of removing the files to the trash with regards to Win98SE and MACs.
(I'm guessing that has something to do with it's trash bin)