Codeigniter not working on IIS -

i trying run codeigniter in iis. able welcome page not able load controller.

what understand that, executing index.php file if give value after in url iis not responding.

for example

<domain>/<folder>/index.php - works

but

<domain>/<folder>/index.php/welcome - doesn't works

what assume in second case instead of executing index.php, iis treating folder , looking script inside index.php/welcome folder.

is there way make work.

the server running on iis 4. (it running on our client machine , don't have option upgrade it. )

thanks in advance