SYMPTOMS
Virtual floppy disk drives may exist on a computer. For example, they may be created by a virtual disk driver. If virtual floppy disk drives exist, the driver for the Floppy Disk Controller (Fdc.sys) may treat them as real floppy disk drives. It may report them to the Plug and Play Manager.
The system then incorrectly assigns extra drive letters for these virtual floppy disk drives in Windows Explorer. Therefore, you may find more than one drive letter for every virtual drive in Windows Explorer. Some of these drive letters do not point to the correct virtual drive.
The following registry override was provided to force Fdc.sys to physically probe the floppy drives to determine whether the floppy drives actually exist or whether they are only virtual drives. If they are virtual drives, it does not report them.
However, because of a bug in the Fdc.sys driver, this override value does not go into effect. Therefore, it is not useful.
HKLM\System\CCS\Services\fdc
ProbeFloppyDevices = 1 (type = DWORD)
RESOLUTION
To resolve this problem, obtain the latest service pack for Microsoft Windows 2000. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
260910 How to obtain the latest Windows 2000 service pack
Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Microsoft Windows 2000 Service Pack 4.