IOCtl Problem.

Hello,
I am writing a driver to create a virtual disk partition using some RAM.
Driver is installed properly and a symblic link at \DosDevice\F: is created.
But when I start using this partition I get an error message,
"F:\ is not accessible
Incorrect function."

After debugging through the code I found that my DispatchIOCtl() is getting
following IOCtl's calls repetedly,
IOCtl command = 0x00074804 IOCTL_STORAGE_MEDIA_REMOVAL
IOCtl command = 0x00070024 IOCTL_DISK_IS_WRITABLE
IOCtl command = 0x00070000 IOCTL_DISK_GET_DRIVE_GEOMETRY
IOCtl command = 0x0007405C Unknown IOCTL
IOCtl command = 0x00074804 IOCTL_STORAGE_MEDIA_REMOVAL

I tried to find out the command using CTL_CODE of ntdddisk.h, but getting
Function value 0x0017 which does not exist.
I am not able to figure out what's the flaw here?
Could you please let me know what is going wrong here.

Thanks in Advance,
~rushikesh.
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Rushikesh Patil.
Persistent Systems Pvt. Ltd.
cell: +(91)98226-39056
http://www.rushikeshpatil.8m.com
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