Page Not Found with ?var=name

[eluser]Tickk[/eluser]
Hi All,
I already have a website runs with some member and their affiliate ID.
The affiliate URL : http://www.mydomain.com/?id=username

I want to recode my website with CI.
Without affiliate id, i can access my website smoothly.
But when i used http://www.mydomain.com/?id=username i got error 404 page not found.

I don't want to change the url syntax because i already have a lot members use it.
Is it posible with CI ?
Or do I miss something here so I got that error ?

Thank you in advance for your helps.
Regards.

[eluser]gullah[/eluser]
http://ellislab.com/codeigniter/user-gui.../urls.html

take a look. there it looks like you need to enable query strings

[eluser]Tickk[/eluser]
i've tried to enable query string.
But i still got error 404

[eluser]Tickk[/eluser]
Ah found it
http://ellislab.com/forums/viewthread/97909/
The query string works now.
Btw thx drewtown