register XPCOM object on windows mozilla version

Hi every body,

i have a probleme to register an xpcom object on windows mozilla.
That's work on compile mozilla version but not on "classical " mozilla
version.
My XPI file copy object xpt and dll file in components directory.  And
when i restart mozilla, object is not recorder.
Then i try to add .autoreg file in program directory, start regxpcom
command on components directory ....
It does'nt work.
Some body has an idear about it ??
Thanks 
Frederic