This is done for performance reasons. Windows XP knows nothing about the nature of a removeable disk. In some cases the media may be removed or changed and Windows will know nothing about it. This is the case with Floppy drives. It is all up to the device and it's drivers. Since the media can be changed at any time Windows can not determine the total and free space without actually reading the disk. With some devices this can take some time. This could produce a delay of several seconds (or more) every time you opened Windows explorer. To avoid these possible delays Microsoft decided not to show this information for removeable drives. In most cases there will be no work around. If one exists it would be in the properties for the device shown in Device Manager.
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