CreateFile error 32 on NTFS

Hi Gurus,

I wrote a file system filer driver to monitor the file access, another user
mode app will do some file verification as soon as the monitored file is
closing, everything works good on a FAT USB drive but yesterday when I got a
NTFS USB drive, I got error 32 in the user mode application when opening the
file. The error is “the process cannot access the file because it is being
used by another process”. I guess it’s something related to the create flag
DesiredAccess and the ShareAccess, I modified these two fields to shareable
and any access, still no luck. Anyone have the same experiences please help,
very appreciated for your hints. thanks in advance.