filter driver 的安装问题

i have written a filter driver,used as lowerfilter of disk.when i
installed the filter driver,i first add registry manually as follow:
1. add keyes under HKLM\\...\\Services\\\"myfilter\",such as,
  \"start\" ,\"ErrorContrl\",\"type\",\"ImagePath\" etc.
2. second, add \"myfilter\" as lowerfilters under
HKLM\\...\\Enum\\Ide\\disk...\\\"gendisk\"\\. here \"gendisk\" is one subkey of
disk...
but when i restarted,i found myfilter.sys wasn\'t be loaded into system.
and \"bluescreen\" appeared.

then i use the method provided by \"ddk\\src\\storage\\filters\\fpfilter\" as
followed,it can be loaded correctly.
1.from \"hardware wizzard\", install a device using \"myfilter\" as its
driver.
2. the same as method 1.

my question is:
why method 2 can success and if using method 1, is the registry key lost
somewhere?

thanks a lot for your help!!!

Hi
  The method 2 \"ddk\\src\\storage\\filters\\fpfilter\" you successed  load your driver as a upper filter,not lower
one!

它确实也可以作为lowerfilter，这个我已经试过了。