Charles Thompson writes of another USB device problem 'solved' by the often recommended work-around: disconnecting and reconnecting the device: 'The SanDisk ImageMate CompactFlash card reader has two indicator lights, one of which blinks to indicate proper USB connection. Every time I use the reader with my G4/450 (running Mac OS 9), that light is on solid (unblinking) and the card will not mount on the desktop. Disconnecting and reconnecting the USB connector clears the problem long enough to get the FlashCard mounted.'

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He contacted SanDisk about this. This was their reply (it does not directly address the reported bug, but may be relevant):

Compact Flash Card Reader For Macbook Pro

We are currently working on an updated driver for use with OS 9. In the meantime, we have a work around that should allow you to use the USB ImageMate CompactFlash drive until the new driver comes out.

Flash Card Application For Windows

Plug the ImageMate into the Mac. Boot the machine. Insert the CompactFlash card into the ImageMate.

or

2. Boot the Mac. Plug the CF card into the ImageMate. Plug the ImageMate with CF card into the Mac.

Best Compact Flash Card Reader For Mac

Explanation: The SanDisk ImageMate uses its own Mass Storage Driver for the ImageMate. Mac OS 9 uses a native Mass Storage Driver. By using the ImageMate and CF as mentioned above, the Mac OS native Mass Storage Driver with not enumerate when the ImageMate is used.